feat(wall-posts): add wall post reading/writing with comments (v1.3.0)

- Add get_wall_posts: read recent wall posts with like/comment counts
- Add create_wall_post: publish new status posts to the wall
- Add add_comment: add comments to wall posts and activities
- like_post already supports both wall posts and activities (v1.2.0)
- Update README.md with new Wall & Activities section
- Update CLAUDE.md with v1.3.0 and tool reorganization
- Update CHANGELOG.md with v1.3.0 release notes
- Add wallpublish and walladdComment documentation to SPEC.md

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

CHANGELOG.md

@@ -10,6 +10,22 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 This project follows Semantic Versioning (SemVer).
 Breaking changes (removed tools, changed parameters) increment the major version.
 
+## [1.3.0] – 2026-04-17
+
+### Added
+- **Wall post reading**: `get_wall_posts` — retrieve recent wall posts with author, text,
+  creation date, like count, liked-by-me flag, and comment count
+- **Wall post writing**: `create_wall_post` — publish a new status post to the wall
+- **Comments**: `add_comment` — add a comment to a wall post or activity
+- All three new wall post tools require user confirmation before calling
+
+### Notes
+- `get_wall_posts` supersedes the activity-listing functionality of `get_activities`
+  (which continues to exist for backward compatibility)
+- `like_post` already supports both wall posts and activities; verified to work
+  with metaIds from both `get_wall_posts` and `get_activities`
+- Post IDs are in the format `wall/<familyid>_<postid>`
+
 ## [1.2.0] – 2026-04-17
 
 ### Added