refactor(tmux): Swift code quality improvements (findings #35-40)

[daiimus]

Summary

Addresses 6 low-severity findings (#35-40) from the comprehensive code review, improving Swift code quality across the tmux integration layer.

• Memory leaks: CADisplayLink retain cycle, scrollIndicator strong capture, key repeat timer #35: Mark 6 log-only notification handlers with // MARK: - Stub Handlers annotation for discoverability
• App userdata dangling pointer — Unmanaged lifetime issue #36: Extract surfaceView(from:) helper — replaces 25 identical ghostty_surface_userdata extraction patterns
• Input handling: open_url null-termination assumption, pressesBegan drops simultaneous keys #37: Extract decodePayload(data:len:) helper — replaces 5 identical UnsafeRawBufferPointer conversion blocks
• deinit Task.detached cleanup may not run #38: Add TmuxId format validation guards to selectPane, pasteTmuxBuffer, closeWindow(windowId:), renameWindow(windowId:), selectWindow — prevents malformed IDs from reaching tmux
• Config migration silently changes line endings #39: handleSessionRenamed now stores the name in @Published sessionName (moved out of stub section); property reset on prepareForReattach
• Ghostty.swift minor issues: search string inconsistency, haptic alloc per-tap, scroll direction, close/deinit double-free #40: Define TmuxNotificationKey enum with 10 typed constants — replaces raw string keys across posting (Ghostty.App.swift) and consuming (SSHSession.swift) sides

Also fixes the double-% bug in paste-buffer command (same as S1 finding #3, independently fixed here since this branch predates PR #131).

Testing

All tests pass (./ci.sh test). Updated tests:

• testSelectPaneWithInvalidPaneIdDoesNotSendCommand — validates new guard behavior
• testOnPaneTapWithMalformedPaneIdIsRejected — validates guard in tap context
• testHandleSessionRenamedUpdatesSessionName — verifies property storage
• testPrepareForReattachClearsTransientState — verifies sessionName reset
• Paste tests updated to use properly formatted %N pane IDs

AI Disclosure

This PR was authored with AI assistance (Claude claude-opus-4.6 via OpenCode).

Closes #130

[Copilot]

Pull request overview

This PR addresses 6 low-severity findings (#35-40) from a comprehensive code review, improving Swift code quality across the tmux integration layer. It extracts common patterns into helpers, adds input validation, centralizes notification keys, and makes a log-only handler functional.

Changes:

• Extracts surfaceView(from:) and decodePayload(data:len:) helpers in Ghostty.App.swift to eliminate 25+ duplicated patterns, adds TmuxId validation guards on 5 functions, and introduces TmuxNotificationKey enum for typed notification userInfo keys
• Promotes handleSessionRenamed from a log-only stub to store the session name in a new @Published sessionName property, with reset in prepareForReattach
• Fixes the double-% bug in the paste-buffer command (same as PR #131 finding #3)

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
Geistty/Sources/Ghostty/Ghostty.App.swift	Extracts surfaceView(from:) and decodePayload(data:len:) helpers; replaces all inline patterns; uses TmuxNotificationKey for all notification userInfo keys
Geistty/Sources/SSH/TmuxSessionManager.swift	Adds TmuxId validation guards to closeWindow, renameWindow, selectWindow, selectPane, pasteTmuxBuffer; promotes handleSessionRenamed with sessionName property; fixes double-% in paste-buffer command
Geistty/Sources/SSH/SSHSession.swift	Replaces all raw string notification userInfo key accesses with TmuxNotificationKey constants
Geistty/Sources/App/GeisttyApp.swift	Defines TmuxNotificationKey enum with 10 typed constants
Geistty/GeisttyTests/TmuxSessionManagerTests.swift	Updates tests for new validation behavior, sessionName storage, and %N-format pane IDs in paste tests

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (1)

Geistty/GeisttyTests/TmuxSessionManagerTests.swift:2251

• The doc comment is stale: it says "should still send the tmux command (fire-and-forget)" but the test now verifies the opposite — the validation guard rejects the invalid pane ID and no command is sent (line 2266). The comment should be updated to match the new behavior, e.g., "selectPane() with an invalid pane ID should be rejected by the validation guard."

    /// Tapping the same pane twice should still send the command and route.
    /// (Idempotent — tmux handles duplicate select-pane gracefully.)

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

[Copilot]

The doc comment at lines 2295-2296 still describes the old pre-guard behavior: "selectPane() with a pane ID that has no numeric component should still send the tmux command (fire-and-forget) but NOT call setActiveTmuxPaneInputOnly." However, the test now verifies the opposite — the guard rejects the invalid pane ID, no command is sent, and setActiveTmuxPaneInputOnly is not called. The comment should be updated to reflect the rejection behavior, e.g., "selectPane() with a pane ID that fails validation should reject the call: no command is sent and setActiveTmuxPaneInputOnly is not called."