v1.2.5

v1.2.5 — Pure Rust: remove Python dependency, clean dead code

Major cleanup:
- Ported transaction ID generation from Python to native Rust
  (src/transaction_id.rs). No more shelling out to python3.
  Fetches X homepage + ondemand.s, parses HTML with regex, does
  cubic bezier + SHA256 + base64 all in Rust. Zero external deps.
- Removed scripts/gen_transaction_id.py
- Removed 4 unused crate dependencies: governor, owo-colors,
  indicatif, async-trait (saves compile time + binary size)
- Removed dead code: unused bookmarks() fn, get_mention_followers(),
  get_bookmarks(), set_media_alt_text(), get_user_posts(),
  get_rate_limits(), last_rate_limit(), includes field on ApiResponse
- Fixed API count minimums: search/replies need min 10 (X API
  requirement), timelines min 5, followers/following min 1
- Zero compiler warnings

Single Rust binary. No Python. No Node. No Docker.