refactor: decouple task lifecycle from issue status (#151)

* refactor: decouple task lifecycle from issue status, add daemon health server

- Remove automatic issue status changes from StartTask (in_progress),
  CompleteTask (in_review), and FailTask (blocked) in task service.
  Issue status is now fully managed by the agent via `multica issue status`.
- Update agent prompt and meta skill to instruct agents to manage issue
  status themselves (in_progress → done/in_review/blocked).
- Add daemon health HTTP server on 127.0.0.1:19514 with /health endpoint
  exposing pid, uptime, agents, and workspaces. Fail fast if port is taken
  (another daemon already running).
- Update `multica status` to check both server and daemon health.
- Add Save button to repos section in workspace settings UI.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* refactor(daemon): simplify prompt, fix runtime config path, improve task error logging

- Slim down BuildPrompt to a minimal hint; detailed workflow now lives in CLAUDE.md/AGENTS.md
- Write CLAUDE.md to workDir root instead of .claude/CLAUDE.md
- Fix git-exclude pattern (.claude → CLAUDE.md)
- Decouple task queue reconciliation from issue status changes (agents manage status via CLI)
- Add diagnostic logging when CompleteTask/FailTask fail due to unexpected task state

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix(task): use task_completed/task_failed inbox notification types

FailTask was sending "agent_blocked" which conflates agent crash with
issue-level blocked status. Align notification types with the new
decoupled model: task_completed and task_failed. Update frontend types
and labels accordingly.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/internal/daemon/execenv/execenv.go

@@ -111,7 +111,7 @@ func Prepare(params PrepareParams, logger *slog.Logger) (*Environment, error) {
 				env.gitRoot = gitRoot
 
 				// Exclude injected directories from git tracking.
-				for _, pattern := range []string{".agent_context", ".claude", "AGENTS.md"} {
+				for _, pattern := range []string{".agent_context", "CLAUDE.md", "AGENTS.md"} {
 					if err := excludeFromGit(workDir, pattern); err != nil {
 						logger.Warn("execenv: failed to exclude from git", "pattern", pattern, "error", err)
 					}