feat(espidf): the components Espressif's own board demos are built from

A header that lives in a registry component and is not on
_MANAGED_COMPONENT_INCLUDES dies at "No such file or directory": the
project template ships no idf_component.yml, so nothing fetches it. That
list covered five display/camera components, which left the pieces the
official Espressif board demos are actually made of unavailable —
verified by compiling a one-include probe for each against staging:

  led_strip.h            FAIL  (the C3-LCDkit knob_panel's WS2812 driver)
  iot_button.h           FAIL  (its BOOT/knob-press handling)
  iot_knob.h             FAIL  (its EC11 quadrature decoder)

esp_lcd_touch_gt911 (the P4 devkit's panel) and esp_codec_dev (every
audio demo on the VoCat and the P4) are added on the same grounds.

Anyone pasting code from esp-dev-kits or esp-bsp hit this on the first
line. Detection is unchanged — the dependency is declared only when the
source actually includes the header.

Tests: ManagedComponentDetectionTests in test_espidf_pure_mode.py, incl.
negative cases (a user's own my_led_strip.h must not match).

backend/app/services/espidf_compiler.py

@@ -898,6 +898,17 @@ class ESPIDFCompiler:
         (r'esp_lcd_touch_cst816s\.h', 'espressif/esp_lcd_touch_cst816s', '*'),
         (r'esp_lcd_gc9a01\.h', 'espressif/esp_lcd_gc9a01', '*'),
         (r'esp_lcd_ek79007\.h', 'espressif/esp_lcd_ek79007', '*'),
+        # The building blocks Espressif's OWN board demos are made of — the
+        # C3-LCDkit knob_panel drives its WS2812 through led_strip and its
+        # EC11 through knob+button, the P4 devkit's panel is a GT911, and
+        # every audio demo on the VoCat/P4 goes through esp_codec_dev. A
+        # visitor pasting official example code hit "No such file or
+        # directory" on all four.
+        (r'led_strip\.h', 'espressif/led_strip', '*'),
+        (r'iot_button\.h', 'espressif/button', '*'),
+        (r'iot_knob\.h', 'espressif/knob', '*'),
+        (r'esp_lcd_touch_gt911\.h', 'espressif/esp_lcd_touch_gt911', '*'),
+        (r'esp_codec_dev\.h', 'espressif/esp_codec_dev', '*'),
     )
 
     def _detect_managed_components(self, code: str) -> dict:

test/backend/unit/test_espidf_pure_mode.py

@@ -140,3 +140,46 @@ class TestJobKeyLanguageVariance(unittest.TestCase):
 
 if __name__ == '__main__':
     unittest.main()
+
+
+class ManagedComponentDetectionTests(unittest.TestCase):
+    """The registry components a sketch's #includes must pull in.
+
+    The template ships no idf_component.yml, so a header that lives in a
+    managed component and is not on this list dies at "No such file or
+    directory" — which is exactly what official Espressif board-demo code
+    did for led_strip / button / knob / GT911 / esp_codec_dev.
+    """
+
+    def setUp(self) -> None:
+        self.comp = make_compiler()
+
+    def test_official_demo_components_are_declared(self) -> None:
+        cases = {
+            '#include "led_strip.h"': 'espressif/led_strip',
+            '#include "iot_button.h"': 'espressif/button',
+            '#include "iot_knob.h"': 'espressif/knob',
+            '#include "esp_lcd_touch_gt911.h"': 'espressif/esp_lcd_touch_gt911',
+            '#include "esp_codec_dev.h"': 'espressif/esp_codec_dev',
+            '#include "esp_camera.h"': 'espressif/esp32-camera',
+            '#include "esp_lcd_gc9a01.h"': 'espressif/esp_lcd_gc9a01',
+            '#include "esp_lcd_st77916.h"': 'espressif/esp_lcd_st77916',
+            '#include "esp_lcd_touch_cst816s.h"': 'espressif/esp_lcd_touch_cst816s',
+            '#include "esp_lcd_ek79007.h"': 'espressif/esp_lcd_ek79007',
+        }
+        for line, component in cases.items():
+            with self.subTest(line=line):
+                self.assertIn(component, self.comp._detect_managed_components(line))
+
+    def test_angle_bracket_form_counts_too(self) -> None:
+        deps = self.comp._detect_managed_components('#include <led_strip.h>')
+        self.assertIn('espressif/led_strip', deps)
+
+    def test_unrelated_source_declares_nothing(self) -> None:
+        src = '#include <stdio.h>\n#include "driver/gpio.h"\nvoid app_main(void) {}'
+        self.assertEqual(self.comp._detect_managed_components(src), {})
+
+    def test_a_similarly_named_header_does_not_match(self) -> None:
+        # "my_led_strip.h" is the user's own file, not the registry component.
+        deps = self.comp._detect_managed_components('#include "my_led_strip.h"')
+        self.assertEqual(deps, {})