docs: update project state through Phase 3

Phase 2: memory, session search, git worktree configured
Phase 3: Telegram gateway connected, DM pairing approved
Phase 4: custom skills created (aws-diagnostics, jira-query, confluence-search, bitbucket-pr)

.planning/ROADMAP.md

@@ -1,6 +1,6 @@
 # Roadmap: ngn-agent
 
-**Current Phase:** None yet — start with Phase 1
+**Current Phase:** Phase 2 — Memory, Git & Session Management
 **Total Phases:** 4
 **v1 Requirements:** 22 mapped — all covered ✓