fix(cli): adopt DA1 sandwich technique for robust OSC color query detection (#986)

Replace ad-hoc environment checks (CI, Warp, tmux, Docker) with a
comprehensive `is_osc_query_unsupported()` pre-screen modelled after
`terminal-colorsaurus`, and implement the DA1 sandwich technique to
detect unsupported terminals at runtime without waiting for timeouts.

Key changes:
- Centralized quirks detection covering CI, Docker, devcontainers,
  Kubernetes, Emacs, GNU Screen, Eterm, tmux, and TERM=dumb
- DA1 sentinel query appended after OSC queries; if its response
  arrives first the terminal doesn't support OSC and we bail immediately
- drain_da1() consumes the trailing DA1 response to prevent leaks
- BEL terminator instead of ST to work around urxvt response bug
- SSH-aware timeout (1000ms vs 200ms local)
- Ported regression test from terminal-colorsaurus issue #38
- Extended test coverage for parsing edge cases

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

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> [!NOTE]
> **Medium Risk**
> Touches low-level `/dev/tty` I/O, raw-mode handling, and timeout/polling logic, so regressions could reintroduce hangs or garbled terminal output in edge-case terminals/environments.
>
> **Overview**
> Makes terminal color detection for the Vite+ CLI header more robust by replacing ad-hoc OSC query handling with a centralized `is_osc_query_unsupported()` pre-screen and a DA1 “sandwich” sentinel to quickly detect terminals that won’t answer OSC color queries.
>
> Reworks `query_terminal_colors` to send BEL-terminated OSC 10/4 queries plus DA1, parse responses from `/dev/tty` via `BufReader` with delimiter-aware reads, apply SSH-aware timeouts, and drain DA1/CSI output to prevent escape-sequence leakage; adds extensive unit tests covering hex/RGB parsing edge cases, BEL termination, stream parsing helpers, and a non-hanging regression test.
>
> <sup>Written by [Cursor Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit 2ca0070. This will update automatically on new commits. Configure [here](https://cursor.com/dashboard?tab=bugbot).</sup>
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Author: Brooooooklyn