Merge CB-594: make supervision and a working fleet possible at the same time

The launchd unit was a CHANGEME template that had never been installed, and it could not have worked if it were: launchd does not source a login shell, so the daemon would have started with no forge or gateway token, and the failure would only appear much later as workers unable to open a PR.

Four parts: a wrapper that execs one login shell in place so the job inherits the secret store; a startup report naming which required secret env vars resolved and which are MISSING, by name only, never a value; the plist filled in with this host's real verified paths; and `redeploy-bridged.sh` detecting the agent and switching stop/start to `launchctl unload -w` / `load -w`, falling back to the existing kill + nohup when it is not installed.

Verified by the lead. My own unpiped build of the branch: 813 tests, BUILD SUCCESS. Trial-merged onto current main (which had moved twice) and rebuilt: Tests run: 822, Failures: 0, Errors: 0, Skipped: 0 — BUILD SUCCESS. All three host paths in the plist exist; no CHANGEME remains; the secret report leaks no values.

An independent reviewer, briefed only from the diff, verified the parts that matter today and said merge. It confirmed live that the unsupervised path is unchanged, that `launchctl list` exits 113 for an absent agent so the detection reads correctly, that the wrapper round-trips arguments containing spaces and quotes and stays a single exec chain, and that neither branch of the secret report can print a value.

Its two open findings only bite once the agent is actually loaded, which has not happened and is the operator's call. Filed as #91 — that must land before the agent is ever installed. The important one is that the script computes its log path from its own location while the plist hard-codes an absolute one; if they ever disagree, the post-restart ERROR check reads the wrong file and reports "ok" while the daemon crash-loops.

The agent is deliberately NOT installed by this merge. Nothing here changes how the daemon runs today.

bridged/src/main/java/dev/ltms/bridged/Bridged.java

@@ -83,6 +83,10 @@ public final class Bridged {
     static void main(String[] args) {
         Path configPath = Path.of(args.length > 0 ? args[0] : "bridged.yaml");
         BridgedConfig cfg = BridgedConfig.load(configPath);
+        // CB-594: report which secret env vars the config actually needs, by name, before anything
+        // else can fail on a silently-empty one. A daemon started without a login shell (launchd)
+        // boots fine either way — this is the only thing that says so out loud.
+        reportRequiredSecrets(cfg);
         // CB-559: `cfg` stays the startup snapshot — every validation and every piece of one-time
         // wiring below reads it, and must, because those decisions cannot be unmade. `config` is the
         // live reference the hot paths read per use. Which keys can actually move is ConfigRef's
@@ -544,6 +548,63 @@ public final class Bridged {
         return target -> presence.isPresent(target) || leads.get().containsKey(target);
     }
 
+    /**
+     * CB-594: which env vars the loaded config actually needs, and why — every non-{@code
+     * subscription} profile's {@code tokenEnv} (a subscription profile never reads one, see
+     * {@link BridgedConfig.Profile#isSubscription()}), plus every profile's {@code gitTokenEnv}
+     * where set (opt-in). Derived from the config, not hard-coded, so a new profile is covered for
+     * free. A var required by more than one profile is one entry naming every profile that needs
+     * it. Deliberately excludes {@code auth.tokenEnv}: that one is already enforced loudly, by a
+     * startup throw, a few lines above this method's call site.
+     *
+     * <p>Package-private and pure (no I/O, no logging) so the derivation is unit-testable without
+     * capturing log output; {@link #reportRequiredSecrets(BridgedConfig)} is the logging caller.
+     */
+    static Map<String, List<String>> requiredSecretEnvVars(BridgedConfig cfg) {
+        Map<String, List<String>> requiredBy = new LinkedHashMap<>();
+        cfg.profiles().forEach((name, profile) -> {
+            if (!profile.isSubscription()) {
+                requiredBy.computeIfAbsent(profile.tokenEnv(), _ -> new ArrayList<>())
+                        .add("profile '" + name + "' tokenEnv");
+            }
+            if (profile.hasGitToken()) {
+                requiredBy.computeIfAbsent(profile.gitTokenEnv(), _ -> new ArrayList<>())
+                        .add("profile '" + name + "' gitTokenEnv");
+            }
+        });
+        return requiredBy;
+    }
+
+    /**
+     * CB-594: log, by name only, which required env vars (see {@link #requiredSecretEnvVars}) are
+     * set in the daemon's own process environment — the environment every profile's {@code
+     * tokenEnv}/{@code gitTokenEnv} is read from at spawn time (see
+     * {@code HerdrPeerLauncher.resolveEnv}). Never logs a value, a prefix, or a length.
+     *
+     * <p>A missing entry only warns — it must never refuse to start. A daemon that boots and says
+     * what is wrong is strictly more useful than one that will not boot at all.
+     */
+    private static void reportRequiredSecrets(BridgedConfig cfg) {
+        Map<String, List<String>> requiredBy = requiredSecretEnvVars(cfg);
+        if (requiredBy.isEmpty()) {
+            log.info("startup secrets: no profile references a token env var — nothing to check");
+            return;
+        }
+        Map<String, String> env = System.getenv();
+        requiredBy.forEach((varName, sources) -> {
+            String value = env.get(varName);
+            if (value != null && !value.isBlank()) {
+                log.info("startup secret {}: set ({})", varName, String.join(", ", sources));
+            } else {
+                log.warn("startup secret {}: MISSING ({}) — the daemon will start anyway, and this "
+                                + "failure stays invisible until a worker actually needs it. Fix "
+                                + "${SHARED_ENV}/tools/secrets.sh and restart bridged from a LOGIN "
+                                + "shell (see scripts/redeploy-bridged.sh).",
+                        varName, String.join(", ", sources));
+            }
+        });
+    }
+
     /**
      * Poll herdr's {@code ping} until it answers or {@link #HERDR_WAIT_SECONDS} elapses (CB-504).
      *