feat: catalog of known apps (bundle ID → default per-pedal key mappings) to pre-fill rules on add

[ericfitz]

Summary

Maintain a catalog of well-known applications (keyed by bundle ID) with default per-pedal key mappings, so that when a user adds a known app in Settings, Footswitch can pre-populate the likely keystrokes for pedal 1 / 2 / 3 instead of leaving them blank. The user is always free to change the suggested defaults — this just removes guesswork for common apps.

The authoritative list of apps, bundle IDs, and key mappings is maintained in this Google Sheet:
https://docs.google.com/spreadsheets/d/1X3lw61pKETU-l1mG2y4ijKo3qt-JOSduF3AdS0lWHNQ/edit

Motivation

Today, adding an app to the rules table (config.rules, see Sources/FootswitchCore/Models/Rule.swift) gives the user an empty SlotActions that they must fill in by hand. For many well-known apps the "right" keystrokes are known and stable (e.g. mute/unmute, next/previous page/slide). Pre-supplying those defaults saves the user from looking up and entering each combo.

Pedal count is independent of the catalog: a single-switch pedal will only ever fire slot 1, so the slot 2/3 defaults are simply unused. But for apps that have distinct actions (separate mute vs. unmute, next vs. prev, as opposed to a single toggle key) we will already know how to populate slots 2 and 3.

Proposed Approach

• Add a bundled, read-only catalog of { bundleID, appName, slots: { 1, 2, 3 } } entries derived from the Google Sheet (e.g. a JSON resource shipped in the app bundle, generated/exported from the sheet).
• When the user adds an app in Settings:
  • If the chosen app's bundle ID matches a catalog entry, pre-fill the per-slot actions from the catalog as the new rule's defaults.
  • If there is no match, behave as today (empty slots).
• Pre-filled values are editable — the catalog only seeds initial defaults; it never overrides a user's saved choice.
• Catalog entries should map cleanly onto the existing Action model (keyCombo for the common case; the schema should also be able to express slots that have no sensible default).

Open Questions / Decisions

• Source-of-truth workflow: how do we go from the Google Sheet to the bundled resource? Manual export + commit, or a small script that fetches/transforms the sheet into the JSON resource? (Lean toward a committed JSON file regenerated by a script so the build has no network dependency.)
• Catalog schema: confirm fields per entry (bundle ID, display name, per-slot action incl. modifiers) and how to represent "no default for this slot."
• Match semantics: exact bundle-ID match only (consistent with RuleResolver), so this stays a pure convenience layer over the existing matching.
• Conflict on add: if the user adds an app they already have a rule for, do we touch existing slots? (Proposed: never overwrite existing user values; only seed brand-new rules.)

Acceptance Criteria

• A bundled catalog of known apps (bundle ID → default per-slot key mappings) exists, sourced from the Google Sheet.
• Adding a known app in Settings pre-fills pedal 1/2/3 defaults from the catalog.
• Adding an unknown app behaves exactly as today (no defaults).
• Pre-filled defaults are fully editable and never override a user's saved configuration.
• A documented, repeatable process exists for regenerating the catalog from the Google Sheet.

Relevant Code

• Sources/FootswitchCore/Models/Rule.swift — Rule { match, appName, slots }
• Sources/FootswitchCore/Models/SlotActions.swift — per-slot Action map
• Sources/FootswitchCore/Models/Action.swift — keyCombo / dictation / shortcut
• Sources/FootswitchCore/RuleResolver.swift — exact bundle-ID matching
• Sources/Footswitch/SettingsView.swift — where apps are added to the rules table