feat(render): auto-detect HDR from media probes, add --sdr flag (#526)

* feat(render): auto-detect HDR from media probes, add --sdr flag

Replace the --hdr opt-in model with automatic detection. When no flags
are passed, the renderer probes all video/image sources and enables HDR
output if any HDR color space is detected. Existing --hdr flag becomes
a force override. New --sdr flag forces SDR output.

Behavior matrix:
  (no flags) + HDR content → HDR output
  (no flags) + SDR content → SDR output
  --hdr → force HDR (defaults to HLG if no HDR sources)
  --sdr → force SDR (skips probing)
  --hdr --sdr → error

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix: align HDR auto-detect docs and tests

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/cli/src/utils/dockerRunArgs.test.ts

@@ -6,7 +6,7 @@ const BASE: DockerRenderOptions = {
   quality: "standard",
   format: "mp4",
   gpu: false,
-  hdr: false,
+  hdrMode: "auto",
   crf: undefined,
   videoBitrate: undefined,
   quiet: false,
@@ -57,9 +57,8 @@ describe("buildDockerRunArgs", () => {
         ...FIXED_INPUT,
         options: {
           ...BASE,
-          workers: 4,
           gpu: true,
-          hdr: true,
+          hdrMode: "force-hdr",
           crf: 18,
           videoBitrate: undefined,
           quiet: true,
@@ -88,8 +87,6 @@ describe("buildDockerRunArgs", () => {
         "standard",
         "--format",
         "mp4",
-        "--workers",
-        "4",
         "--crf",
         "18",
         "--quiet",
@@ -102,17 +99,28 @@ describe("buildDockerRunArgs", () => {
   // Regression for the original PR feedback: --hdr was silently dropped from
   // the docker arg array. Keep this assertion explicit (in addition to the
   // snapshot above) so the failure message points directly at the flag.
-  it("forwards --hdr to the container when hdr is enabled", () => {
+  it("forwards --hdr to the container when hdrMode is force-hdr", () => {
     const args = buildDockerRunArgs({
       ...FIXED_INPUT,
-      options: { ...BASE, hdr: true },
+      options: { ...BASE, hdrMode: "force-hdr" },
     });
     expect(args).toContain("--hdr");
+    expect(args).not.toContain("--sdr");
   });
 
-  it("omits --hdr when hdr is disabled", () => {
+  it("forwards --sdr to the container when hdrMode is force-sdr", () => {
+    const args = buildDockerRunArgs({
+      ...FIXED_INPUT,
+      options: { ...BASE, hdrMode: "force-sdr" },
+    });
+    expect(args).toContain("--sdr");
+    expect(args).not.toContain("--hdr");
+  });
+
+  it("omits --hdr and --sdr when hdrMode is auto", () => {
     const args = buildDockerRunArgs({ ...FIXED_INPUT, options: BASE });
     expect(args).not.toContain("--hdr");
+    expect(args).not.toContain("--sdr");
   });
 
   it("requests host GPU passthrough only when gpu is enabled", () => {
@@ -140,7 +148,7 @@ describe("buildDockerRunArgs", () => {
         format: "webm",
         workers: 8,
         gpu: true,
-        hdr: true,
+        hdrMode: "force-hdr",
         crf: 16,
         videoBitrate: undefined,
         quiet: true,

packages/cli/src/utils/dockerRunArgs.ts

@@ -24,7 +24,7 @@ export interface DockerRenderOptions {
   format: "mp4" | "webm" | "mov";
   workers?: number;
   gpu: boolean;
-  hdr: boolean;
+  hdrMode: "auto" | "force-hdr" | "force-sdr";
   crf?: number;
   videoBitrate?: string;
   quiet: boolean;
@@ -59,6 +59,7 @@ export function buildDockerRunArgs(input: DockerRunArgsInput): string[] {
     ...(options.videoBitrate ? ["--video-bitrate", options.videoBitrate] : []),
     ...(options.quiet ? ["--quiet"] : []),
     ...(options.gpu ? ["--gpu"] : []),
-    ...(options.hdr ? ["--hdr"] : []),
+    ...(options.hdrMode === "force-hdr" ? ["--hdr"] : []),
+    ...(options.hdrMode === "force-sdr" ? ["--sdr"] : []),
   ];
 }