Request validation and resilience improvements (#864)

### Security: Input validation & path safety
- **Reject local file references by default** in package parsing — only allow when explicitly opted in by the service (`ParseFlags::kAllowLocalReferences`) and validated by an `ILocalRefPolicy` (fail-closed: no policy = rejected)
- **`DataRootLocalRefPolicy`** restricts local ref paths to the server's data root via canonical path prefix matching
- **Validate attachment hashes** in compute HTTP handlers — decompresses and re-hashes each attachment at ingestion time to reject tampered payloads
- **Path traversal validation** for worker descriptions (`pathvalidation.h`) — rejects absolute paths, `..` components, Windows reserved device names, and invalid filename characters
- **Harden CbPackage parsing** against corrupt inputs — overflow-safe attachment count, bounds checks on local ref offset/size, graceful failure instead of `ZEN_ASSERT` for untrusted data
- **Harden legacy package parser** — reject zero-size binary fields, missing mappers, and optionally validate resolved attachment hashes
- **Bounds check in `CbPackageReader::MarshalLocalChunkReference`** — detect when `MakeFromFile` silently clamps offset+size to file size

### Reliability: Lock consolidation & bug fixes
- **Consolidate three action map locks into one** (`m_ActionMapLock`) — eliminates deadlock risk from multi-lock ordering, simplifies state transitions, and fixes a race where newly enqueued actions were briefly invisible to `GetActionResult`/`FindActionResult`
- **Fix infinite loop in `BaseRunnerGroup::SubmitActions`** when actions exceed total runner capacity — cap round-robin at `TotalCapacity` and default unassigned results to "No capacity"
- **Fix `MakeSafeAbsolutePathInPlace` for UNC paths** — `\server\share` now correctly becomes `\?\UNC\server\share` instead of `\?\server\share`
- **Fix `max_retries=0`** — previously fell through to the default of 3; now correctly means "no retries"

### New: ManagedProcessRunner
- Cross-platform process runner backed by `SubprocessManager` — uses async exit callbacks instead of polling, delegates CPU/memory metrics to the manager's built-in sampler
- `ProcessGroup` (JobObject on Windows, process group on POSIX) for bulk cancellation on shutdown
- `--managed` flag on `zen exec inproc` to select this runner
- Refactored monitor thread lifecycle — `StartMonitorThread()` now called from derived constructors to avoid calling virtual functions from base constructor

### Process management
- **Suppress crash dialogs** via `JOB_OBJECT_UILIMIT_ERRORMODE` + `SEM_NOGPFAULTERRORBOX` in both `WindowsProcessRunner` and `JobObject::Initialize` — prevents WER/Dr. Watson modal dialogs from blocking the monitor thread
- **CREATE_SUSPENDED → AssignProcessToJobObject → ResumeThread** pattern in `WindowsProcessRunner` — ensures job object assignment before process execution
- **Move stdout/stderr callbacks to `Spawn()` parameters** in `SubprocessManager` — prevents race where early output could be missed before callback installation
- Consistent PID logging across all runner types

### Test infrastructure
- **`zentest-appstub`**: Added `Fail` (configurable exit code) and `Crash` (abort / nullptr deref) test functions
- **Compute integration tests**: exit code handling, auto-retry exhaustion, manual reschedule after failure, mixed success/failure queues, crash handling (abort + nullptr), crash auto-retry, immediate query visibility after enqueue
- **Package format tests**: truncated header, bad magic, attachment count overflow, truncated data, local ref rejection/acceptance, policy enforcement (inside/outside root, traversal, no-policy fail-closed)
- **Legacy package parser tests**: empty input, zero-size binary, hash resolution with/without mapper, hash mismatch detection
- **UNC path tests** for `MakeSafeAbsolutePath`

### Misc
- ANSI color helper macros (`ZEN_RED`, `ZEN_BRIGHT_WHITE`, etc.) and `ZEN_BOLD`/`ZEN_DIM`/etc.
- Generic `fmt::formatter` for types with free `ToString` functions
- Compute dashboard: truncated hash display with monospace font and hover for full value
- Renamed `usonpackage_forcelink` → `cbpackage_forcelink`
- Compute enabled by default in xmake config (releases still explicitly disable)

2 files changed, 42 insertions, 5 deletions

diff --git a/src/zencore/include/zencore/compactbinarypackage.h b/src/zencore/include/zencore/compactbinarypackage.h
index 64b62e2c0..148c0d3fd 100644
--- a/src/zencore/include/zencore/compactbinarypackage.h
+++ b/src/zencore/include/zencore/compactbinarypackage.h
@@ -278,10 +278,10 @@ public:
 	 * @return The attachment, or null if the attachment is not found.
 	 * @note The returned pointer is only valid until the attachments on this package are modified.
 	 */
-	const CbAttachment* FindAttachment(const IoHash& Hash) const;
+	[[nodiscard]] const CbAttachment* FindAttachment(const IoHash& Hash) const;
 
 	/** Find an attachment if it exists in the package. */
-	inline const CbAttachment* FindAttachment(const CbAttachment& Attachment) const { return FindAttachment(Attachment.GetHash()); }
+	[[nodiscard]] const CbAttachment* FindAttachment(const CbAttachment& Attachment) const { return FindAttachment(Attachment.GetHash()); }
 
 	/** Add the attachment to this package. */
 	inline void AddAttachment(const CbAttachment& Attachment) { AddAttachment(Attachment, nullptr); }
@@ -336,17 +336,26 @@ private:
 	IoHash								  ObjectHash;
 };
 
+/** In addition to the above, we also support a legacy format which is used by
+ * the HTTP project store for historical reasons. Don't use the below functions
+ * for new code.
+ */
 namespace legacy {
 	void SaveCbAttachment(const CbAttachment& Attachment, CbWriter& Writer);
 	void SaveCbPackage(const CbPackage& Package, CbWriter& Writer);
 	void SaveCbPackage(const CbPackage& Package, BinaryWriter& Ar);
-	bool TryLoadCbPackage(CbPackage& Package, IoBuffer Buffer, BufferAllocator Allocator, CbPackage::AttachmentResolver* Mapper = nullptr);
+	bool TryLoadCbPackage(CbPackage&					 Package,
+						  IoBuffer						 Buffer,
+						  BufferAllocator				 Allocator,
+						  CbPackage::AttachmentResolver* Mapper			= nullptr,
+						  bool							 ValidateHashes = false);
 	bool TryLoadCbPackage(CbPackage&					 Package,
 						  BinaryReader&					 Reader,
 						  BufferAllocator				 Allocator,
-						  CbPackage::AttachmentResolver* Mapper = nullptr);
+						  CbPackage::AttachmentResolver* Mapper			= nullptr,
+						  bool							 ValidateHashes = false);
 }  // namespace legacy
 
-void usonpackage_forcelink();  // internal
+void cbpackage_forcelink();	 // internal
 
 }  // namespace zen
diff --git a/src/zencore/include/zencore/logging.h b/src/zencore/include/zencore/logging.h
index 3427991d2..1608ad523 100644
--- a/src/zencore/include/zencore/logging.h
+++ b/src/zencore/include/zencore/logging.h
@@ -90,6 +90,34 @@ using zen::ConsoleLog;
 using zen::ErrorLog;
 using zen::Log;
 
+////////////////////////////////////////////////////////////////////////
+// Color helpers
+
+#define ZEN_RED(str)	 "\033[31m" str "\033[0m"
+#define ZEN_GREEN(str)	 "\033[32m" str "\033[0m"
+#define ZEN_YELLOW(str)	 "\033[33m" str "\033[0m"
+#define ZEN_BLUE(str)	 "\033[34m" str "\033[0m"
+#define ZEN_MAGENTA(str) "\033[35m" str "\033[0m"
+#define ZEN_CYAN(str)	 "\033[36m" str "\033[0m"
+#define ZEN_WHITE(str)	 "\033[37m" str "\033[0m"
+
+#define ZEN_BRIGHT_RED(str)		"\033[91m" str "\033[0m"
+#define ZEN_BRIGHT_GREEN(str)	"\033[92m" str "\033[0m"
+#define ZEN_BRIGHT_YELLOW(str)	"\033[93m" str "\033[0m"
+#define ZEN_BRIGHT_BLUE(str)	"\033[94m" str "\033[0m"
+#define ZEN_BRIGHT_MAGENTA(str) "\033[95m" str "\033[0m"
+#define ZEN_BRIGHT_CYAN(str)	"\033[96m" str "\033[0m"
+#define ZEN_BRIGHT_WHITE(str)	"\033[97m" str "\033[0m"
+
+#define ZEN_BOLD(str)		   "\033[1m" str "\033[0m"
+#define ZEN_UNDERLINE(str)	   "\033[4m" str "\033[0m"
+#define ZEN_DIM(str)		   "\033[2m" str "\033[0m"
+#define ZEN_ITALIC(str)		   "\033[3m" str "\033[0m"
+#define ZEN_STRIKETHROUGH(str) "\033[9m" str "\033[0m"
+#define ZEN_INVERSE(str)	   "\033[7m" str "\033[0m"
+
+////////////////////////////////////////////////////////////////////////
+
 #if ZEN_BUILD_DEBUG
 #	define ZEN_CHECK_FORMAT_STRING(fmtstr, ...)      \
 		while (false)                                 \