build(ffmpeg): make ffmpeg-next an unconditional dependency

The decoder is intrinsic to what beat does, so gating it behind an
off-by-default feature produced a green build that excluded the core
capability — a false signal. Remove the `ffmpeg` feature from beat-data and
beat-cli, drop the cfg gates on the decode module and the no-ffmpeg
process_one fallback, and revert the readme build note. Building and testing
now require the FFmpeg dev libraries, as they should.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/beat-cli/Cargo.toml

@@ -10,11 +10,6 @@ authors.workspace = true
 name = "beat"
 path = "src/main.rs"
 
-[features]
-# Enables the ffmpeg-next decoder in beat-data. Required to process real videos;
-# left off by default so the workspace builds without the FFmpeg dev libraries.
-ffmpeg = ["beat-data/ffmpeg"]
-
 [dependencies]
 beat-entities = { workspace = true }
 beat-core = { workspace = true }

crates/beat-cli/src/process.rs

@@ -19,7 +19,6 @@ pub fn file_key(path: &Path) -> Result<FileKey> {
 }
 
 /// Decode a video and run the full pipeline into a [`VideoResult`].
-#[cfg(feature = "ffmpeg")]
 async fn decode_and_process<L: LlmClient + Sync>(
     path: &Path,
     config: &Config,
@@ -47,15 +46,6 @@ async fn decode_and_process<L: LlmClient + Sync>(
     Ok(result)
 }
 
-#[cfg(not(feature = "ffmpeg"))]
-async fn decode_and_process<L: LlmClient + Sync>(
-    _path: &Path,
-    _config: &Config,
-    _llm: &L,
-) -> anyhow::Result<VideoResult> {
-    anyhow::bail!("beat was built without the `ffmpeg` feature; rebuild with --features ffmpeg")
-}
-
 /// Process one video file end-to-end: claim → decode → describe → summarise →
 /// write → record. Returns `true` if processed, `false` if skipped (already
 /// done / in progress and `force` is not set).

crates/beat-data/Cargo.toml

@@ -6,17 +6,6 @@ rust-version.workspace = true
 license.workspace = true
 authors.workspace = true
 
-[features]
-# The ffmpeg-next decoder is OFF by default so the rest of the workspace builds
-# and tests without the FFmpeg development libraries installed. CI (which
-# installs the libs) builds with `--all-features`; production builds and
-# `beat run` against real videos use `--features ffmpeg` (forwarded from
-# beat-cli's `ffmpeg` feature).
-default = []
-ffmpeg = ["dep:ffmpeg-next"]
-# Placeholder for the future ONNX/YOLO object-detection signal.
-object-detection = []
-
 [dependencies]
 beat-entities = { workspace = true }
 beat-core = { workspace = true }
@@ -35,7 +24,7 @@ notify = { workspace = true }
 redb = { workspace = true }
 walkdir = { workspace = true }
 tempfile = { workspace = true }
-ffmpeg-next = { workspace = true, optional = true }
+ffmpeg-next = { workspace = true }
 
 [dev-dependencies]
 wiremock = { workspace = true }

crates/beat-data/src/lib.rs

@@ -1,14 +1,12 @@
 //! I/O implementations: ffmpeg decoding, LLM HTTP client, filesystem watcher,
 //! processed-file ledger, and sidecar writers.
 
-#[cfg(feature = "ffmpeg")]
 pub mod decode;
 pub mod ledger;
 pub mod llm;
 pub mod output;
 pub mod watcher;
 
-#[cfg(feature = "ffmpeg")]
 pub use decode::{FfmpegAudioSource, FfmpegFrameSource};
 pub use ledger::RedbLedger;
 pub use llm::HttpLlmClient;

readme.md

@@ -121,13 +121,7 @@ beat --config ./beat.toml run /path/to/video.mkv
 ## Building
 
 ```sh
-cargo build --release --features ffmpeg
-```
-
-The `ffmpeg` feature (off by default) compiles the in-process `ffmpeg-next` decoder. It is gated so the rest of the workspace — and its tests — build without the FFmpeg development libraries installed; CI builds with `--all-features`. A binary built without the feature runs but refuses to process videos, prompting a rebuild with `--features ffmpeg`. To build and test the non-decoder crates without FFmpeg:
-
-```sh
-cargo test            # workspace tests, no FFmpeg libs required
+cargo build --release
 ```
 
 `beat` links against the FFmpeg shared libraries (libavcodec, libavformat, libavutil, libswscale) through `ffmpeg-next`. These must be present at build and run time. On Fedora:

script/deploy.sh

@@ -76,8 +76,8 @@ resolve_secret() {
 }
 
 # --- Build once for this commit ---
-info "building beat (release, ffmpeg feature)"
-run cargo build --release --manifest-path "${REPO_ROOT}/Cargo.toml" -p beat-cli --features ffmpeg
+info "building beat (release)"
+run cargo build --release --manifest-path "${REPO_ROOT}/Cargo.toml" -p beat-cli
 readonly BINARY="${REPO_ROOT}/target/release/beat"
 
 deploy_worker() {