fix: harden terminal and CLI behavior

[m1ngsama]

What

• decode coalesced and split terminal input without losing navigation or pasted text
• make plain document rendering, pager handoff, and theme mutations consistently ANSI-free
• add width-aware compact event output and stricter CLI validation/exit semantics
• cancel TUI view work on quit and restore the terminal on q, Ctrl-C, SIGINT, SIGTERM, and SIGHUP
• harden schedule authentication/session ownership against late async completion
• adapt the docs reader to current Documents HTML checkboxes/details and cancel in-flight docs requests
• report browser launcher and update-check failures with actionable nonzero exits

Impact

Existing commands and both bin names remain compatible. Normal q exits 0; Ctrl-C/SIGINT exits 130, SIGTERM 143, and SIGHUP 129. No package version, dependency, README, release workflow, authentication protocol, or publishing change is included.

Checks

• TZ=UTC npm run check on Node 20.12.2, Node 22.18.0, and the local Node runtime
• 54 test files / 718 tests, CLI contract, package consumer smoke, audit 0
• current Documents fixture: 188/188 budget statuses preserved, no residual input/details/summary HTML
• fresh tarball install: 73 files, both bins, no legacy bin/ directory
• deterministic status/docs/events CLI and narrow-width acceptance
• real PTY tests for q/Ctrl-C/signals, classic docs q/j/l, split/coalesced keys, pending network cancellation, and exact terminal restoration
• independent strict diff review: no blocker