docs(docs): update ctrl‑a keybinding docs to use omp‑session and add omp‑session script description

docs/ai/omp.mdx

@@ -168,7 +168,7 @@ Both count as done only when the full artifact is pasted in the chat.
 | Entry point | Source | What it does |
 | --- | --- | --- |
 | fish completions | `dot_config/fish/completions/omp.fish` | `omp completions fish \| source` generates completions at load time |
-| <kbd>Ctrl</kbd> <kbd>A</kbd> | fish `fish_user_key_bindings` → `_agents_bind`, zsh `keybinds.zsh` | fish: the `agents` tv cable, with `omp` first; zsh: launches `omp` from the prompt |
+| <kbd>Ctrl</kbd> <kbd>A</kbd> | fish `fish_user_key_bindings`, zsh `keybinds.zsh` → `dot_local/bin/executable_omp-session` | Resumes or starts omp for the current repo: default branch → the session written in the last 3 hours, else the `omp-sessions` tv cable; other branches → that branch's newest session, else a new one. See [omp-session](/shell/scripts#omp-session) |
 | `launch_omp_livediff_overlay` | `dot_local/bin/executable_launch_omp_livediff_overlay`, fish function of the same name | Opens omp as a kitty overlay on the current window with a `livediff` vsplit beside it, focus kept on omp. Needs `KITTY_LISTEN_ON` (kitty remote control). |
 | `lc-elir [root]` | `dot_local/bin/executable_lc-elir`, fish function | fzf multi-picks numbered LeetCode files (`1365.slug.js`/`.ts`) with a bat preview and runs `omp -p "/leetcode-eli5 <file>"` on each |