chore: remove dead code and unused parameters

types.nim:
- Remove unused constants: BusJsonlPath, BlobsDir, WorkersDir

worker.nim:
- Remove unused 'by' and 'comment' parameters from approve()

Note: skills-5ax (unused imports in db.nim) no longer applies -
strutils is used for toHex in genOid fallback path.

Closes: skills-t9ub, skills-5ax, skills-fdu, skills-ghlb

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/worker.nim

@@ -119,7 +119,7 @@ proc status(state: string = "", stale: bool = false,
   else:
     render()
 
-proc approve(taskId: string, by: string = "", comment: string = "") =
+proc approve(taskId: string) =
   ## Approve completed work (IN_REVIEW → APPROVED)
   discard validateTaskId(taskId)
   let db = openBusDb()
@@ -328,9 +328,7 @@ when isMainModule:
                      "watch": "Refresh every 2s"}],
     [start, help = {"task": "Task ID (reads from context if empty)"}],
     [done, help = {"skipRebase": "Skip rebase (after manual conflict resolution)"}],
-    [approve, help = {"taskId": "Task to approve",
-                      "by": "Reviewer name",
-                      "comment": "Approval comment"}],
+    [approve, help = {"taskId": "Task to approve"}],
     [requestChanges, cmdName = "request-changes",
      help = {"taskId": "Task to reject",
              "comment": "Feedback for agent"}],

src/worker/types.nim

@@ -61,9 +61,6 @@ const
   # Paths
   WorkerStateDir* = ".worker-state"
   BusDbPath* = ".worker-state/bus.db"
-  BusJsonlPath* = ".worker-state/bus.jsonl"
-  BlobsDir* = ".worker-state/blobs"
-  WorkersDir* = ".worker-state/workers"
   WorktreesDir* = "worktrees"
   ContextFileName* = ".worker-ctx.json"