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)

1 files changed, 28 insertions, 8 deletions

diff --git a/src/zenserver/frontend/html/pages/compute.js b/src/zenserver/frontend/html/pages/compute.js
index d1a880954..2eb4d4e9b 100644
--- a/src/zenserver/frontend/html/pages/compute.js
+++ b/src/zenserver/frontend/html/pages/compute.js
@@ -24,6 +24,12 @@ function formatTime(date)
 	return date.toLocaleTimeString([], { hour: "2-digit", minute: "2-digit", second: "2-digit" });
 }
 
+function truncateHash(hash)
+{
+	if (!hash || hash.length <= 15) return hash;
+	return hash.slice(0, 6) + "\u2026" + hash.slice(-6);
+}
+
 function formatDuration(startDate, endDate)
 {
 	if (!startDate || !endDate) return "-";
@@ -305,11 +311,7 @@ export class Page extends ZenPage
 	{
 		const workerIds = data.workers || [];
 
-		if (this._workers_table)
-		{
-			this._workers_table.clear();
-		}
-		else
+		if (!this._workers_table)
 		{
 			this._workers_table = this._workers_host.add_widget(
 				Table,
@@ -320,6 +322,7 @@ export class Page extends ZenPage
 
 		if (workerIds.length === 0)
 		{
+			this._workers_table.clear();
 			return;
 		}
 
@@ -349,6 +352,9 @@ export class Page extends ZenPage
 					id,
 				);
 
+				// Worker ID column: monospace for hex readability
+				row.get_cell(5).style("fontFamily", "'SF Mono', 'Cascadia Mono', Consolas, 'DejaVu Sans Mono', monospace");
+
 				// Make name clickable to expand detail
 				const cell = row.get_cell(0);
 				cell.tag().text(name).on_click(() => this._toggle_worker_detail(id, desc));
@@ -546,6 +552,11 @@ export class Page extends ZenPage
 				["LSN", "queue", "status", "function", "started", "finished", "duration", "worker ID", "action ID"],
 				Table.Flag_FitLeft|Table.Flag_PackRight|Table.Flag_Sortable|Table.Flag_AlignNumeric, -1
 			);
+
+			// Right-align hash column headers to match data cells
+			const hdr = this._history_table.inner().firstElementChild;
+			hdr.children[7].style.textAlign = "right";
+			hdr.children[8].style.textAlign = "right";
 		}
 
 		// Entries arrive oldest-first; reverse to show newest at top
@@ -560,7 +571,10 @@ export class Page extends ZenPage
 			const startDate = filetimeToDate(entry.time_Running);
 			const endDate = filetimeToDate(entry.time_Completed ?? entry.time_Failed);
 
-			this._history_table.add_row(
+			const workerId = entry.workerId || "-";
+			const actionId = entry.actionId || "-";
+
+			const row = this._history_table.add_row(
 				lsn,
 				queueId,
 				status,
@@ -568,9 +582,15 @@ export class Page extends ZenPage
 				formatTime(startDate),
 				formatTime(endDate),
 				formatDuration(startDate, endDate),
-				entry.workerId || "-",
-				entry.actionId || "-",
+				truncateHash(workerId),
+				truncateHash(actionId),
 			);
+
+			// Hash columns: force right-align (AlignNumeric misses hex strings starting with a-f),
+			// use monospace for readability, and show full value on hover
+			const mono = "'SF Mono', 'Cascadia Mono', Consolas, 'DejaVu Sans Mono', monospace";
+			row.get_cell(7).style("textAlign", "right").style("fontFamily", mono).attr("title", workerId);
+			row.get_cell(8).style("textAlign", "right").style("fontFamily", mono).attr("title", actionId);
 		}
 	}