feat(main): firmware integration by wiring all three modules into main.c and updating the full test runner

[Rohith-Kalarikkal]

Summary

Completes the Sprint 2 firmware integration by wiring all three modules into main.c and updating the full test runner. main.c now has a clean superloop that calls sensor_init(), motor_init(), reads all sensors every 10 ms, applies brake-override motor control logic, and rate-limits UART Teleplot logging to every 100 ms. test_runner.c is updated to include all 69 Sprint 2 tests across the three modules using the handoff .inc pattern so future sprints can add tests without touching test_runner.c. Both CMakeLists.txt files are confirmed correct and all stub HAL headers are stable.

Type of Change

• 🆕 New feature / user story
• 🐛 Bug fix
• ♻️ Refactor (no behaviour change)
• 📝 Documentation only
• 🔧 CI/CD or tooling change
• 🔒 Security fix

Related Issue

Closes #31 #32

Changes Made

• Updated core/src/main.c - Sprint 2 additions: sensor_init() and motor_init() calls with blink-on-failure error handling, main_loop_run() calling sensor_read_all() every 10 ms, motor_control_update() implementing brake-overrides-throttle safety rule, uart_log_sensors() emitting Teleplot-format >label:value\n lines every 100 ms, and system_hal_init() setting up stub HAL handles with correct ARR=3599 for 20 kHz PWM at 72 MHz
• Updated tests/test_runner.c - added extern declarations for all 63 Sprint 2 tests across all three modules; replaced individual RUN_TEST() calls with #include "handoff/dev1_tests.inc", #include "handoff/dev2_tests.inc", and #include "handoff/dev3_tests.inc" in the correct s_active_module context so setUp()/tearDown() dispatches correctly for each module group
• Updated tests/test_placeholder.c - no functional changes; confirmed Sprint 1 framework tests still pass
• Confirmed CMakeLists.txt (root) - FIRMWARE_SOURCES list includes all three new module .c files; linker script path correct
• Confirmed tests/CMakeLists.txt - TEST_SOURCES includes test_sensor_hal.c, test_motor_ctrl.c, test_protocol_prep.c, and test_runner.c; MOCK_SOURCES includes all five mock files; FIRMWARE_SOURCES_UNDER_TEST includes sensor_hal.c, motor_ctrl.c, and fault_logger.c
• Confirmed all drivers/STM32_HAL/stm32f1xx_hal*.h stub headers - no changes required; all peripheral types used by Sprint 2 modules are already defined

How to Test This PR

1. Checkout the branch: git checkout feat/main-build
2. Confirm PRs 1, 2, and 3 have all merged - check git log --oneline develop and verify commits from feat/sensor-hal, feat/motor-ctrl, and feat/fault-log are present
3. Verify all handoff files exist: ls tests/handoff/ - must show dev1_tests.inc, dev2_tests.inc, dev3_tests.inc
4. Build the firmware: cmake --build build - must complete with 0 errors and 0 warnings
5. Build and run the full test suite: cd tests && mkdir -p build && cd build && cmake .. -DCMAKE_BUILD_TYPE=Debug && make && ./test_runner
6. Confirm final output shows exactly 69 Tests 0 Failures 0 Ignored
7. Run Cppcheck across all sources: cppcheck --error-exitcode=1 -I core/inc core/src/

Testing Done by Author

• Unit tests written for new/changed code
• All existing tests pass locally (cd Tests/build && ./test_runner → 0 Failures)
• Cppcheck passes locally (cppcheck --error-exitcode=1 -I core/Inc core/src/)
• Code compiled successfully (cmake --build build)
• Tested in Wokwi simulation (if applicable)
• UART output verified (if applicable)
• No new compiler warnings (-Wall -Wextra clean)

Code Quality Checklist

• Code follows naming conventions from 06_CODING_STANDARDS.md
• All public functions have Doxygen-style comments (@brief, @param, @retval)
• No magic numbers — all constants are in ev_config.h
• All function parameters are validated (null checks where applicable)
• Return values of all called functions are checked
• All switch statements have a default case
• All if/for/while blocks use { braces even for single lines

Documentation

• README.md updated if new setup steps are needed
• Inline /* TODO: */ comments added for any deferred work

Screenshots / Logs (if applicable)

./tests/build/test_runner
..............................................................................
 
-----------------------
69 Tests 0 Failures 0 Ignored 
OK

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**Reviewer checklist:**
- [ ] Code logic is correct and matches the linked issue requirements
- [ ] Tests are meaningful (not just "assert(1 == 1)")
- [ ] No obvious security or safety issues
- [ ] Comments are clear and accurate