refactor(cli): centralize TUI keybindings via bubbles/key

[Soph]

https://entire.io/gh/entireio/cli/trails/249

Introduce a shared keyMap (cmd/entire/cli/keys.go) so the activity, dispatch, and search TUIs all match keys and render help text from one source of truth, replacing scattered string literals like "esc", "ctrl+c", and "q".

Entire-Checkpoint: 7611ae68730a

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Note

Low Risk
Low risk refactor that mainly replaces scattered key string comparisons and hardcoded help text with bubbles/key bindings; potential risk is minor behavior drift if any prior key strings differed from the new bindings.

Overview
Centralizes TUI keybindings by introducing cmd/entire/cli/keys.go as a single source of truth for common actions (quit/back/search/confirm/navigation).

Updates the activity, dispatch, and search TUIs to use key.Matches(...) against the shared bindings instead of ad-hoc msg.String() checks, and rewires footer/help rendering to pull key labels/descriptions from the same bindings (removing local constants like tuiEscKey).

^{Reviewed by Cursor Bugbot for commit 1e5d0e3. Configure here.}

[Copilot]

Pull request overview

This PR centralizes Bubble Tea TUI keybindings into a single shared keyMap so the activity, dispatch, and search TUIs match on the same bindings and can render consistent help text.

Changes:

• Added cmd/entire/cli/keys.go defining shared keys bindings (quit/back/search/confirm/navigation).
• Updated search_tui.go to use key.Matches against shared bindings and to render help text using binding help metadata.
• Updated activity_tui.go and dispatch_tui.go to use the shared quit/back bindings instead of local string checks.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
cmd/entire/cli/search_tui.go	Replaces scattered key string literals with shared bindings; updates footer/help rendering accordingly.
cmd/entire/cli/keys.go	Introduces the shared TUI key map as the single source of truth.
cmd/entire/cli/dispatch_tui.go	Uses shared quit/back bindings for cancel behavior and removes local tuiEscKey.
cmd/entire/cli/activity_tui.go	Uses shared quit/back bindings and updates footer help to use binding metadata.