Add synchronous=NORMAL, 64MB cache, temp_store=MEMORY, and 256MB mmap
PRAGMAs to halve fsync overhead and improve write throughput. Replace
per-symbol DELETE+INSERT embedding writes with batch executemany inserts,
use cursor.lastrowid instead of extra SELECT queries for ID retrieval,
and consolidate multiple commits per file into a single transaction.

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

Add SSE (Server-Sent Events) transport option to the MCP server, allowing
a single shared instance to serve multiple MCP host clients over HTTP.

- Add --transport, --port, and --host CLI arguments
- Extract build_arg_parser() so tests validate the real CLI contract
- Update README with SSE server setup and MCP host configuration examples
- Update uv.lock

- README: restore `uv build` newline that was clobbered into
  `uv build# Clone the repo`, and drop the duplicated clone/install
  block that landed inside the Development section
- README: add a security note that the SSE endpoint is unauthenticated
  and should stay bound to 127.0.0.1
- server.py: move `import argparse` to the module-level imports and
  drop the string-quoted return type on build_arg_parser
- tests: drop the `pytest.importorskip("sqlite_vec")` (server is already
  imported at module top, so the skip never fires) and the
  `importlib.reload(server)` (no test mutates module source); call
  `server_mod.main()` directly

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

feat: add SSE transport support and refactor CLI arg parsing