Phase 1: Windows log collection + full-text search

Extends the agent, ingest, storage, api, and web with Windows Event
Log/ETW sourcing and Tantivy-backed free-text search, per the approved
Phase 1 plan.

- CLAUDE.md: materialized on disk (never existed as a file before) with
  a new Phase 1 "done looks like" section.
- agent: Windows Event Log (EvtSubscribe) and ETW sources, Windows
  service wrapper (install/uninstall/run-service), both feature- and
  target_os-gated so Linux builds/tests/clippy stay unaffected. Also
  fixed two pre-existing Phase 0 clippy gaps (dead-code on
  default-features-only builds, a type-inference edge case) found while
  testing every feature combination properly for the first time.
  UNVERIFIED on real Windows -- no Windows toolchain existed anywhere in
  the build environment; flagged prominently in three places.
- proto/ingest: new record_id field, assigned once server-side in
  ingest's gRPC front end so ClickHouse and Tantivy agree on the same ID
  for the same record.
- storage: record_id column + bloom filter index, verified against a
  live ClickHouse.
- search: new service, Tantivy index, rskafka consumer as an independent
  second consumer group on the same Redpanda topic ingest already reads.
- api/web: new /search endpoint and page, sharing the query page's
  result-table shape and component.
- hack/windows-fixture: sends realistic Windows-shaped data straight to
  ingest, so the pipeline's handling of it is verifiable without a
  Windows host.

Verified end-to-end on the live docker-compose stack: the same record_id
comes back from both /query and /search for the same log line, including
for windows-fixture's synthetic Windows Event Log data. Real bugs found
and fixed along the way: api/Dockerfile missing proto/ in its build
context, search's logs being completely silent (RUST_LOG gap), and
search/target/ missing from .gitignore/.dockerignore.

search/src/main.rs

@@ -0,0 +1,67 @@
+mod config;
+mod consumer;
+mod grpc;
+mod index;
+mod offsets;
+
+pub mod logsv1 {
+    tonic::include_proto!("sentry.logs.v1");
+}
+pub mod searchv1 {
+    tonic::include_proto!("sentry.search.v1");
+}
+
+use anyhow::{Context, Result};
+use config::Config;
+use index::SearchIndex;
+use std::sync::Arc;
+use tonic::transport::Server;
+
+/// Matches /transport/provision-topics.sh's default
+/// REDPANDA_TOPIC_PARTITIONS -- documented cross-component contract, not
+/// discovered dynamically. See consumer.rs.
+const DEFAULT_PARTITION_COUNT: i32 = 6;
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    tracing_subscriber::fmt()
+        .with_env_filter(tracing_subscriber::EnvFilter::from_default_env())
+        .init();
+
+    let cfg = Arc::new(Config::load().context("loading config")?);
+
+    let index = Arc::new(
+        SearchIndex::open_or_create(&cfg.index_path).context("opening tantivy index")?,
+    );
+
+    let partition_count: i32 = std::env::var("REDPANDA_TOPIC_PARTITIONS")
+        .ok()
+        .and_then(|s| s.parse().ok())
+        .unwrap_or(DEFAULT_PARTITION_COUNT);
+
+    let consumer_cfg = Arc::clone(&cfg);
+    let consumer_index = Arc::clone(&index);
+    let consumer_handle = tokio::spawn(async move {
+        if let Err(e) = consumer::run(consumer_cfg, consumer_index, partition_count).await {
+            tracing::error!(error = %e, "redpanda consumer exited with error");
+        }
+    });
+
+    let addr = cfg
+        .grpc_listen_addr
+        .parse()
+        .context("parsing GRPC_LISTEN_ADDR")?;
+    tracing::info!(addr = %cfg.grpc_listen_addr, "search gRPC server listening");
+
+    let search_server = grpc::SearchServer::new(Arc::clone(&index));
+    Server::builder()
+        .add_service(searchv1::search_service_server::SearchServiceServer::new(
+            search_server,
+        ))
+        .serve(addr)
+        .await
+        .context("gRPC server failed")?;
+
+    consumer_handle.abort();
+    Ok(())
+}