fix: harden terminal probes across platforms

[subinium]

Summary

• restrict automatic terminal capability probes to identified direct terminal emulators
• skip query traffic for non-TTY streams, TERM=dumb, and tmux/screen unless explicitly forced
• add SLT_FORCE_TERMINAL_QUERIES and SLT_DISABLE_TERMINAL_QUERIES overrides
• emit Kitty keyboard push/pop sequences directly so crossterm's legacy Windows API cannot abort terminal cleanup
• make optional Windows console-mode teardown best-effort so cursor, paste, and alternate-screen restoration always continues
• make the run_static signature regression test compile-only so it never opens a live terminal under a PTY test runner
• add blocking macOS and Windows test jobs to both pull-request CI and the release gate
• document the query policy and record the changes under Unreleased

Why

A real-PTY run exposed two compatibility hazards: a compile-signature test could emit terminal query sequences, and a silent or generic PTY host could leave the reply pump racing the first byte of user input. Automatic probing now requires a direct-terminal identity, while environment fallbacks remain available without terminal I/O.

The first Windows CI run exposed a separate cleanup bug: crossterm 0.28 reports Kitty keyboard commands as unsupported through its legacy Windows API. The next run exposed that mouse cleanup can also report Initial console modes not set when panic cleanup has no initialized session. Either error previously returned before focus, bracketed paste, cursor, and alternate-screen cleanup ran. SLT now writes the standard Kitty ANSI protocol bytes directly and treats optional console-mode teardown as best-effort while preserving core restoration.

Validation

• cargo fmt -- --check
• cargo check --all-features
• cargo clippy --all-features -- -D warnings
• cargo test --all-features (847 core unit tests plus integration and doctests)
• cargo check --examples --all-features
• typos
• cargo check -p superlighttui --no-default-features
• cargo check -p slt-wasm --target wasm32-unknown-unknown
• cargo hack check -p superlighttui --each-feature --no-dev-deps (29 combinations)
• cargo audit (1,174 advisories loaded, no vulnerabilities)
• cargo deny check
• cargo check -p superlighttui --features full,pty-test --target x86_64-pc-windows-gnu
• real PTY smoke tests for TERM=dumb and an unidentified generic xterm-256color host; no query/control bytes were emitted
• workflow YAML parsed successfully

Release note

This is an Unreleased post-v0.22.3 hardening change. It does not retag or mutate the published v0.22.3 artifact.