feat: initial commit — BMAD tooling, Claude memories, firmware scaffold

Adds the complete project foundation:
- BMAD BMM workflow tooling (_bmad/)
- Claude slash commands, skills, and project memories (.claude/)
- ESP32 firmware scaffold (PlatformIO + Waveshare e-ink driver)
- .gitignore excluding _bmad-output/ and .pio/ build artifacts

Planning artifacts (PRD, architecture, epics) are intentionally not
tracked — they live in _bmad-output/ per project convention.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

_bmad/bmb/config.yaml

@@ -0,0 +1,13 @@
+# BMB Module Configuration
+# Generated by BMAD installer
+# Version: 6.2.2
+# Date: 2026-03-26T03:59:30.025Z
+
+bmad_builder_output_folder: "{project-root}/_bmad-output/skills"
+bmad_builder_reports: "{project-root}/_bmad-output/reports"
+
+# Core Configuration Values
+user_name: Matt.edholm
+communication_language: English
+document_output_language: English
+output_folder: "{project-root}/_bmad-output"