Add command documentation and improve daemon UX

- Added human-readable uptime formatting (51m 59s vs 3119.4 seconds)
- Fixed daemon stop race condition with SIGKILL
- Added markdown docs for 19 commands: blocked, comments, compact, daemon,
  delete, dep, epic, export, import, label, list, quickstart, rename-prefix,
  renumber, reopen, repos, restore, stale, sync
- Closed: bd-159, bd-152, bd-168
- Deleted test issues: bd-144, bd-145

Amp-Thread-ID: https://ampcode.com/threads/T-9f7c3fed-62de-4bcd-a059-8c1b77cdb841
Co-authored-by: Amp <amp@ampcode.com>

commands/restore.md

@@ -0,0 +1,28 @@
+---
+description: Restore full history of compacted issue from git
+argument-hint: <issue-id>
+---
+
+Restore full history of a compacted issue from git version control.
+
+When an issue is compacted, the git commit hash is saved. This command:
+
+1. Reads the compacted_at_commit from the database
+2. Checks out that commit temporarily
+3. Reads the full issue from JSONL at that point in history
+4. Displays the full issue history (description, events, etc.)
+5. Returns to the current git state
+
+## Usage
+
+`bd restore bd-42`
+
+This is **read-only** - it does not modify the database or git state.
+
+Useful for:
+- Reviewing old issues after compaction
+- Recovering forgotten context
+- Audit trails
+- Historical research
+
+Requires git repository with issue history.