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/core/bmad-init/resources/core-module.yaml

@@ -0,0 +1,25 @@
+code: core
+name: "BMad Core Module"
+
+header: "BMad Core Configuration"
+subheader: "Configure the core settings for your BMad installation.\nThese settings will be used across all installed bmad skills, workflows, and agents."
+
+user_name:
+  prompt: "What should agents call you? (Use your name or a team name)"
+  default: "BMad"
+  result: "{value}"
+
+communication_language:
+  prompt: "What language should agents use when chatting with you?"
+  default: "English"
+  result: "{value}"
+
+document_output_language:
+  prompt: "Preferred document output language?"
+  default: "English"
+  result: "{value}"
+
+output_folder:
+  prompt: "Where should output files be saved?"
+  default: "_bmad-output"
+  result: "{project-root}/{value}"