chore: pre-release cleanup (gitignore, dedup PDFs, drop obsolete script)

- .gitignore: add `.intern/` so internal design notes / decisions /
  roadmaps stay out of the public repo on every clone, and drop the
  stale `examples/esp32-c6-devkitc-multi-midi2/` line that conflicted
  with the tracked content under that path.
- library.json: extend `export.exclude` with `.intern/*` and
  `scripts/*` so PlatformIO never bundles them into a release zip.
- docs/coverage.md: bump header from v0.1.0 to v0.2.0, refresh midi2
  C99 reference to v0.3.3, rewrite the "Zero external dependencies"
  section as "Dependencies" (single declared dep on midi2), remove
  the cross-link to the internal design spec.
- scripts/vendor_midi2.sh: removed. The script copied
  midi2/dist/midi2.{h,c} into src/ -- exactly the vendoring the v0.2.0
  refactor eliminated. CMake `MIDI2_LOCAL_PATH` covers the only
  legitimate offline use case.
- Dedup hardware datasheets across recipes that share boards, keeping
  one canonical copy per board:
    - ESP32-P4 datasheet kept in esp32-p4-devkit-bridge2-midi2/board/
    - ESP32-S3 schematic kept in esp32-s3-devkitc-usb-midi2/board/
    - RP2350-USB-A schematic kept in waveshare-rp2350-usb-a-midi2/board/
    - T-Display S3 PDFs kept in t-display-s3-midi2/board/
- t-display-s3-shield-host-midi2/README.md updated to point at the
  schematic in the sibling device recipe via a relative link.

Author: sauloverissimo

.gitignore

@@ -14,13 +14,17 @@ build-*/
 *.pdb
 *.swp
 *~
-examples/esp32-c6-devkitc-multi-midi2/
 CMakeCache.txt
 CMakeFiles/
 cmake_install.cmake
 Makefile
 compile_commands.json
-.gitignore
+
+# Internal-only material that does not ship to the Arduino Library
+# Manager / PlatformIO Registry. Kept untracked here so contributors
+# do not accidentally push design notes, decision logs, or roadmap
+# drafts to the public repo.
+.intern/
 
 # ESP-IDF generated artifacts and on-demand component clones.
 # fetch_tinyusb.sh drops the TinyUSB PR #3571 fork into idf/external/tinyusb;

docs/coverage.md

@@ -1,24 +1,29 @@
-# Feature Coverage Map — midi2_cpp v0.1.0 → MIDI 2.0 specs
+# Feature Coverage Map — midi2_cpp v0.2.0 → MIDI 2.0 specs
 
 Maps every public midi2_cpp API to the corresponding MIDI 2.0 spec section
-and the backing midi2 C99 v0.3.0 function. For the cross-comparison vs
-AM_MIDI2.0Lib / ni-midi2 / cmidi2, see the design spec §4.
+and the backing midi2 C99 v0.3.3 function.
 
-## Zero external dependencies
+## Dependencies
 
-`midi2_cpp` depends on nothing outside its own source tree:
+`midi2_cpp` declares a single dependency, [midi2](https://github.com/sauloverissimo/midi2)
+(the portable C99 core), and resolves it through whichever package manager
+fits the host build:
+
+- Arduino Library Manager: `depends=midi2 (>=0.3.3)` in `library.properties`.
+- PlatformIO: `dependencies."sauloverissimo/midi2": "^0.3.3"` in `library.json`.
+- ESP-IDF Component Manager: `idf_component.yml` declaration plus `midi2` in `REQUIRES`.
+- CMake: `find_package(midi2 0.3.3 CONFIG)` -> `FetchContent_Declare(midi2 GIT_TAG v0.3.3)` fallback.
+
+Beyond midi2, nothing is pulled in by default:
 
-- midi2 C99 vendored stb-style at `src/midi2.{h,c}` (one source of truth,
-  versioned together).
 - No git submodules — `git clone` is the install.
-- No USB stack pulled in (TinyUSB, native USB, PIO-USB, libDaisy USBMidi
-  are all caller-supplied).
-- No `<Arduino.h>`, `pico/time.h`, `esp_timer.h`, or any platform header
-  in the library translation units.
+- No USB stack (TinyUSB, native USB, PIO-USB, libDaisy USBMidi are all caller-supplied).
+- No `<Arduino.h>`, `pico/time.h`, `esp_timer.h`, or any platform header in the library translation units.
 - No clock or RNG dependency — caller injects through public hooks.
 
-Anywhere C++17 + CMake reach, the library compiles and self-tests with
-no network access after the initial clone.
+Anywhere C++17 + CMake reach, the first configure pulls midi2 once via
+FetchContent (or picks it up through `find_package` if installed); subsequent
+rebuilds and tests run offline.
 
 ## Platform contract
 
@@ -232,7 +237,7 @@ calls a platform symbol it did not receive.
 | `ByteStreamConverter::reset()` | clear running status | re-init via `midi2_conv_init` |
 | `ByteStreamConverter::setGroup(g)` | change UMP group | `state->group` |
 
-## Out of scope for v0.1.0
+## Out of scope for v0.2.0
 
 - USB transport stack (TinyUSB / native USB / Adafruit_TinyUSB / Teensy
   USB / libDaisy USBMidi). Lives in the caller — see the Platform

examples/esp32-p4-devkit-bridge-midi2/board/ESP32-P4-WIFI6-DEV-KIT-datasheet.pdf

@@ -96,7 +96,7 @@ Default `115200 8N1`.
 | GP38 | LCD backlight (PWM, channel 7, 22 kHz) |
 | GP0 (BOOT) | Hold during reset/plug-in to enter download mode |
 
-The Shield's other modules (PCM5102 DAC, 2× MPR121 capacitive touch, microSD, PCA9535 I/O extender, QWIIC) are not used here; they remain available for future variants. Schematic at [`board/SCH_T-Display-S3-MIDI_V1.1.pdf`](board/SCH_T-Display-S3-MIDI_V1.1.pdf).
+The Shield's other modules (PCM5102 DAC, 2× MPR121 capacitive touch, microSD, PCA9535 I/O extender, QWIIC) are not used here; they remain available for future variants. Schematic at [`../t-display-s3-midi2/board/SCH_T-Display-S3-MIDI_V1.1.pdf`](../t-display-s3-midi2/board/SCH_T-Display-S3-MIDI_V1.1.pdf) (canonical copy in the sibling device recipe).
 
 ## Validation