Term Coder v1.28.2

Fixes the v1.28.1 update failure and the preview warnings.

v1.28.1 was broken — its .aip was missing index.html, so updating failed with "The entry file index.html is missing from the archive." This release's archive contains the entry file, style.css, app.json, and the icon at the root (verified), and the release build now derives its file list from index.html + app.json so this class of bug cannot recur.

Preview warnings fixed — detection probes no longer log a warning per failed probe (25 per scan when the terminal capability is off). Expected outcomes are silent and the scan short-circuits.

Includes everything from v1.28.0/v1.28.1: chatoss launch as the only agent launch path (opencode / claude-code / codex), the Install chatoss command guidance, legacy default migration, and the restored stylesheet.