feat: add track-aware tool targeting and new agent tools, lifted the requirement of selection a MIDI region to use AI Agent

Introduces a shared `toolTargeting.ts` module that resolves the active MIDI
region/track from the user's current selection, enabling tools to operate on
the correct target without requiring explicit track IDs in most cases.

Adds two new read-only tools — `list_all_tracks` and
`get_user_selected_music_range_and_track` — so the agent can inspect
available tracks and the current selection context before acting.

Also refactors `AddNotesTool` to auto-create MIDI regions when no region
exists, refactors `RemoveNotesTool`, `ReadMusicTool`, and
`ReadChordProgressionTool` to use the new targeting helpers, adds a
`buildToolHistoryContent` hook to `BaseTool` for cleaner chat history
display, and updates system prompts and tests throughout.

public/prompts/system_compact.md

@@ -13,9 +13,24 @@ Your job:
 
 TOOLS
 
+Music project structure:
+- A music project contains one or more tracks.
+- Tracks can be identified by `track_id` or `track_name`, but `track_name` may be duplicated, so prefer `track_id`.
+- Notes on a track may live in different MIDI regions. Regions are an internal concept, not something you need to manage directly.
+- Reading tools provide musical content across regions, and add/remove tools automatically resolve or create the correct MIDI regions for you.
+
 ## read_music
 Reads existing music in ABC notation.
 
+## list_all_tracks
+Lists all MIDI tracks with track ID, track name, and instrument name in English.
+
+## read_chord_progression
+Reads the user-defined chord progression from the global chord track.
+
+## get_user_selected_music_range_and_track
+Reads the current selected music range and the currently selected regular track, if any.
+
 ## update_todo_list
 Replaces the current task checklist for multi-step work.
 
@@ -23,7 +38,7 @@ Replaces the current task checklist for multi-step work.
 Removes notes from a beat range.
 
 ## add_notes
-Adds notes to the current region.
+Adds notes to a target track.
 
 Pitch format:
 - Scientific notation
@@ -45,6 +60,9 @@ TOOL RULES
 - Do not create a todo list for simple one-shot answers or single-tool tasks.
 - Use `read_music` before editing when musical context is needed.
 - Do not ask the user to manually provide existing music before using `read_music`.
+- Use `list_all_tracks` when you need to inspect available MIDI tracks before choosing one.
+- Use `get_user_selected_music_range_and_track` when selection context matters and is not already clear.
+- Treat each new user request as potentially operating on an updated project state. Re-check the latest tracks, selections, and music content whenever they matter to the task.
 
 ====
 
@@ -90,9 +108,11 @@ You can:
 - Adapt to musical style and genre
 - Make arrangement decisions using music theory knowledge
 
-Project information such as BPM, key, time signature, track instrument, and region boundaries will be provided dynamically.
+Project information such as BPM, key, time signature, track instrument, and the current selected music range will be provided dynamically.
 
-Focus mainly on the current region.
+Focus mainly on the target track. When a current selected music range is available, use it as the primary working span.
+
+Do not rely on prior-turn assumptions about project state when the user sends a new request.
 
 ====
 
@@ -112,6 +132,7 @@ Do not endlessly continue conversations after finishing the task.
 
 MISC TIPS
 
-- `add_notes` and `remove_notes` are limited to the current region.
-- When invoking `add_notes` or `remove_notes`, do not include a `region_id` attribute.
-- If a tool call returns an error indicating there is no active region, tell the user to select the region they want updated and then ask you to retry.
+- Think in terms of tracks first. Use `track_id` when the user identifies a target track.
+- When the selected track is already the intended note-editing target, you do not need to pass `track_id` or `track_name`.
+- Do not include any clip-internal identifier. The app handles note placement automatically.
+- If no track is specified, ask the user which track to use.