clients: expand Go, Python, Rust client APIs

- Add TOTP enrollment/confirmation/removal to all clients
- Add password change and admin set-password endpoints
- Add account listing, status update, and tag management
- Add audit log listing with filter support
- Add policy rule CRUD operations
- Expand test coverage for all new endpoints across clients
- Fix .gitignore to exclude built binaries

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.claude/skills/checkpoint/SKILL.md

@@ -4,5 +4,5 @@
 2. Run `go test ./...`  abort if failures
 3. Run `go vet ./...`
 4. Run `git add -A && git status`  show user what will be committed
-5. Ask user for commit message
+5. Generate an appropriate commit message based on your instructions.
 6. Run `git commit -m "<message>"` and verify with `git log -1`