refactor: update search tool to match Obsidian CLI spec

Removed obsidian_search_with_context tool (not in CLI spec)
Updated obsidian_search to use exact CLI parameter names:
- query (required) - Search query text
- path (optional) - Limit search to folder path
- limit (optional) - Max number of files to return
- total (optional) - Return match count instead of file list
- case (optional) - Case sensitive search
- format (optional) - Output format: text or json (default: text)

Changed parameter names to match CLI:
- folder → path
- caseSensitive → case
- Added: total flag for match counts
- Removed: contextLines (not in CLI)

Files updated:
- src/tools/search.ts: Simplified to single search tool
- src/validation/schemas.ts: Updated searchSchema parameters
- manifest.json: Removed search_with_context, updated description
- tasks.md: Marked T048 as REMOVED

Total tools: 20 (was 21)
- User Story 1: 9 tools
- User Story 2: 11 tools (was 12)

Build: ✅ 0 errors
Validation: ✅ Manifest passes

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

specs/001-obsidian-mcp-bundle/tasks.md

@@ -108,8 +108,8 @@
 ### Implementation for User Story 2
 
 - [X] T046 [P] [US2] Create obsidian_search tool in src/tools/search.ts
-- [X] T047 [P] [US2] Define Zod schema for search parameters (query, folder, limit, caseSensitive)
-- [X] T048 [P] [US2] Create obsidian_search_with_context tool in src/tools/search.ts
+- [X] T047 [P] [US2] Define Zod schema for search parameters (query, path, limit, case, total)
+- [X] T048 [P] [US2] REMOVED - Search with context (not in Obsidian CLI spec)
 - [X] T049 [P] [US2] Create obsidian_get_backlinks tool in src/tools/links.ts
 - [X] T050 [P] [US2] Define Zod schema for backlinks parameters (file/path, counts)
 - [X] T051 [P] [US2] Create obsidian_get_outgoing_links tool in src/tools/links.ts