fix: preserve UVC format compatibility

AGENTS.md

@@ -674,3 +674,16 @@ downstream appsrc dropping.
 - [x] Stop default downstream appsrc leaking on the UAC speech path; shredded chunks are worse than modest added latency for calls.
 - [ ] Reinstall/restart Theia services so `/etc/lesavka/uvc.env` is refreshed from `640x480 @ 20fps` to `1280x720 @ 30fps`.
 - [ ] Re-run manual Google Meet before trusting mirrored probe calibration; verify speech is intelligible and video cadence is stable by eye.
+
+## 0.17.37 UVC Format Compatibility Checklist
+
+Context: after 0.17.36, Google Meet showed `Video Format Not Supported`. The client correctly
+captured the UI-selected `720p@30` profile, but it emitted those frames into a server UVC gadget still
+advertising `640x480 @ 20fps`. USB camera consumers require advertised caps and frame payloads to
+match; otherwise the feed is rejected before we can evaluate smoothness or sync.
+
+- [x] Preserve UI-selected capture quality as the source capture profile.
+- [x] Restore safe default UVC emission to the negotiated server gadget profile so browsers see frames matching the camera format they negotiated.
+- [x] Keep `LESAVKA_CAM_EMIT_UI_PROFILE=1` as an explicit lab-only opt-in until the server can reconfigure the UVC gadget from the UI/session profile.
+- [x] Keep `LESAVKA_CAM_LOCK_TO_SERVER_PROFILE=1` as a safety override that wins over experimental UI-profile emission.
+- [ ] Add a real server-side UVC profile reconfigure path before making UI-selected quality drive the gadget-advertised output format.

Cargo.lock

@@ -1652,7 +1652,7 @@ checksum = "09edd9e8b54e49e587e4f6295a7d29c3ea94d469cb40ab8ca70b288248a81db2"
 
 [[package]]
 name = "lesavka_client"
-version = "0.17.36"
+version = "0.17.37"
 dependencies = [
  "anyhow",
  "async-stream",
@@ -1686,7 +1686,7 @@ dependencies = [
 
 [[package]]
 name = "lesavka_common"
-version = "0.17.36"
+version = "0.17.37"
 dependencies = [
  "anyhow",
  "base64",
@@ -1698,7 +1698,7 @@ dependencies = [
 
 [[package]]
 name = "lesavka_server"
-version = "0.17.36"
+version = "0.17.37"
 dependencies = [
  "anyhow",
  "base64",

client/Cargo.toml

@@ -4,7 +4,7 @@ path                    = "src/main.rs"
 
 [package]
 name                    = "lesavka_client"
-version                 = "0.17.36"
+version                 = "0.17.37"
 edition                 = "2024"
 
 [dependencies]

client/src/app/session_lifecycle.rs

@@ -237,7 +237,7 @@ impl LesavkaClientApp {
                     width = cfg.width,
                     height = cfg.height,
                     fps = cfg.fps,
-                    "📸 using server camera caps as codec/fallback; launcher camera quality remains authoritative"
+                    "📸 using negotiated server UVC caps for emitted format; launcher quality still controls local capture"
                 );
             }
             let ep = vid_ep.clone();

client/src/input/camera.rs

@@ -83,6 +83,7 @@ mod tests {
                 ("LESAVKA_CAM_HEIGHT", Some("720")),
                 ("LESAVKA_CAM_FPS", Some("30")),
                 ("LESAVKA_CAM_LOCK_TO_SERVER_PROFILE", None),
+                ("LESAVKA_CAM_EMIT_UI_PROFILE", None),
             ],
             || assert_eq!(resolved_capture_profile(Some(cfg)), (1280, 720, 30)),
         );
@@ -90,8 +91,8 @@ mod tests {
 
     #[test]
     #[serial]
-    /// UI-selected launcher quality is the source of truth for the camera uplink.
+    /// UVC output must match the gadget profile that browsers negotiate.
-    fn negotiated_output_profile_follows_launcher_quality_by_default() {
+    fn negotiated_output_profile_matches_server_uvc_contract_by_default() {
         let cfg = CameraConfig {
             codec: CameraCodec::Mjpeg,
             width: 640,
@@ -104,6 +105,36 @@ mod tests {
                 ("LESAVKA_CAM_HEIGHT", Some("720")),
                 ("LESAVKA_CAM_FPS", Some("30")),
                 ("LESAVKA_CAM_LOCK_TO_SERVER_PROFILE", None),
+                ("LESAVKA_CAM_EMIT_UI_PROFILE", None),
+            ],
+            || {
+                let capture_profile = resolved_capture_profile(Some(cfg));
+                assert_eq!(capture_profile, (1280, 720, 30));
+                assert_eq!(
+                    resolved_output_profile(Some(cfg), capture_profile),
+                    (640, 480, 20)
+                );
+            },
+        );
+    }
+
+    #[test]
+    #[serial]
+    /// Keeps UI-profile emission explicit until the server can reconfigure UVC.
+    fn explicit_ui_profile_emission_keeps_lab_mode_available() {
+        let cfg = CameraConfig {
+            codec: CameraCodec::Mjpeg,
+            width: 640,
+            height: 480,
+            fps: 20,
+        };
+        temp_env::with_vars(
+            [
+                ("LESAVKA_CAM_WIDTH", Some("1280")),
+                ("LESAVKA_CAM_HEIGHT", Some("720")),
+                ("LESAVKA_CAM_FPS", Some("30")),
+                ("LESAVKA_CAM_LOCK_TO_SERVER_PROFILE", None),
+                ("LESAVKA_CAM_EMIT_UI_PROFILE", Some("1")),
             ],
             || {
                 let capture_profile = resolved_capture_profile(Some(cfg));
@@ -118,8 +149,8 @@ mod tests {
 
     #[test]
     #[serial]
-    /// Keeps the explicit lab lock available for controlled gadget debugging.
+    /// The safety lock wins if both experimental flags are set.
-    fn explicit_server_profile_lock_keeps_lab_mode_available() {
+    fn explicit_server_profile_lock_wins_over_ui_emission() {
         let cfg = CameraConfig {
             codec: CameraCodec::Mjpeg,
             width: 640,
@@ -132,6 +163,7 @@ mod tests {
                 ("LESAVKA_CAM_HEIGHT", Some("720")),
                 ("LESAVKA_CAM_FPS", Some("30")),
                 ("LESAVKA_CAM_LOCK_TO_SERVER_PROFILE", Some("1")),
+                ("LESAVKA_CAM_EMIT_UI_PROFILE", Some("1")),
             ],
             || {
                 let capture_profile = resolved_capture_profile(Some(cfg));

client/src/input/camera/capture_pipeline.rs

@@ -291,7 +291,10 @@ fn resolved_output_profile(
     capture_profile: (u32, u32, u32),
 ) -> (u32, u32, u32) {
     match cfg {
-        Some(cfg) if env_flag_enabled("LESAVKA_CAM_LOCK_TO_SERVER_PROFILE") => {
+        Some(cfg)
+            if env_flag_enabled("LESAVKA_CAM_LOCK_TO_SERVER_PROFILE")
+                || !env_flag_enabled("LESAVKA_CAM_EMIT_UI_PROFILE") =>
+        {
             (cfg.width, cfg.height, cfg.fps.max(1))
         }
         _ => capture_profile,

common/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name                    = "lesavka_common"
-version                 = "0.17.36"
+version                 = "0.17.37"
 edition                 = "2024"
 build                   = "build.rs"
 

server/Cargo.toml

@@ -10,7 +10,7 @@ bench                   = false
 
 [package]
 name                    = "lesavka_server"
-version                 = "0.17.36"
+version                 = "0.17.37"
 edition                 = "2024"
 autobins                = false
 

testing/tests/client_launcher_runtime_contract.rs

@@ -171,6 +171,7 @@ fn launcher_webcam_quality_selection_reaches_preview_and_relay_env() {
     assert!(DEVICE_TEST_SRC.contains("capsfilter caps=\\\"video/x-raw"));
     assert!(CAMERA_SRC.contains("fn resolved_capture_profile"));
     assert!(CAMERA_SRC.contains("LESAVKA_CAM_LOCK_TO_SERVER_PROFILE"));
+    assert!(CAMERA_SRC.contains("LESAVKA_CAM_EMIT_UI_PROFILE"));
     assert!(LAUNCHER_MOD_SRC.contains("\"LESAVKA_CAM_WIDTH\""));
     assert!(LAUNCHER_MOD_SRC.contains("\"LESAVKA_CAM_H264_KBIT\""));
 }