Harden deployment and fix PEN-01

- Fix Bearer token extraction to validate prefix (PEN-01)
- Add TestExtractBearerFromRequest covering PEN-01 edge cases
- Fix flaky TestRenewToken timing (2s → 4s lifetime)
- Move default config/install paths to /srv/mcias
- Add RUNBOOK.md for operational procedures
- Update AUDIT.md with penetration test round 4

Security: extractBearerFromRequest now uses case-insensitive prefix
validation instead of fixed-offset slicing, rejecting non-Bearer
Authorization schemes that were previously accepted.

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

dist/install.sh

@@ -6,7 +6,7 @@
 # This script must be run as root. It:
 #   1. Creates the mcias system user and group (idempotent).
 #   2. Copies binaries to /usr/local/bin/.
-#   3. Creates /etc/mcias/ and /var/lib/mcias/ with correct permissions.
+#   3. Creates /srv/mcias/ with correct permissions.
 #   4. Installs the systemd service unit.
 #   5. Prints post-install instructions.
 #
@@ -25,8 +25,7 @@ set -eu
 # Configuration
 # ---------------------------------------------------------------------------
 BIN_DIR="/usr/local/bin"
-CONF_DIR="/etc/mcias"
-DATA_DIR="/var/lib/mcias"
+SRV_DIR="/srv/mcias"
 MAN_DIR="/usr/share/man/man1"
 SYSTEMD_DIR="/etc/systemd/system"
 SERVICE_USER="mcias"
@@ -114,23 +113,19 @@ for bin in mciassrv mciasctl mciasdb mciasgrpcctl; do
     install -m 0755 -o root -g root "$src" "$BIN_DIR/$bin"
 done
 
-# Step 3: Create configuration directory.
-info "Creating $CONF_DIR"
-install -d -m 0750 -o root -g "$SERVICE_GROUP" "$CONF_DIR"
+# Step 3: Create service directory.
+info "Creating $SRV_DIR"
+install -d -m 0750 -o "$SERVICE_USER" -g "$SERVICE_GROUP" "$SRV_DIR"
 
 # Install example config files; never overwrite existing configs.
 for f in mcias.conf.example mcias.env.example; do
     src="$SCRIPT_DIR/$f"
-    dst="$CONF_DIR/$f"
+    dst="$SRV_DIR/$f"
     if [ -f "$src" ]; then
-        install -m 0640 -o root -g "$SERVICE_GROUP" "$src" "$dst" 2>/dev/null || true
+        install -m 0640 -o "$SERVICE_USER" -g "$SERVICE_GROUP" "$src" "$dst" 2>/dev/null || true
     fi
 done
 
-# Step 4: Create data directory.
-info "Creating $DATA_DIR"
-install -d -m 0750 -o "$SERVICE_USER" -g "$SERVICE_GROUP" "$DATA_DIR"
-
 # Step 5: Install systemd service unit.
 if [ -d "$SYSTEMD_DIR" ]; then
     info "Installing systemd service unit to $SYSTEMD_DIR"
@@ -175,26 +170,26 @@ Next steps:
 
    # Self-signed (development / personal use):
    openssl req -x509 -newkey ed25519 -days 3650 \\
-     -keyout /etc/mcias/server.key \\
-     -out    /etc/mcias/server.crt \\
+     -keyout /srv/mcias/server.key \\
+     -out    /srv/mcias/server.crt \\
      -subj   "/CN=auth.example.com" \\
      -nodes
-   chmod 0640 /etc/mcias/server.key
-   chown root:mcias /etc/mcias/server.key
+   chmod 0640 /srv/mcias/server.key
+   chown mcias:mcias /srv/mcias/server.key /srv/mcias/server.crt
 
 2. Copy and edit the configuration file:
 
-   cp /etc/mcias/mcias.conf.example /etc/mcias/mcias.conf
-   \$EDITOR /etc/mcias/mcias.conf
-   chmod 0640 /etc/mcias/mcias.conf
-   chown root:mcias /etc/mcias/mcias.conf
+   cp /srv/mcias/mcias.conf.example /srv/mcias/mcias.toml
+   \$EDITOR /srv/mcias/mcias.toml
+   chmod 0640 /srv/mcias/mcias.toml
+   chown mcias:mcias /srv/mcias/mcias.toml
 
 3. Set the master key passphrase:
 
-   cp /etc/mcias/mcias.env.example /etc/mcias/env
-   \$EDITOR /etc/mcias/env           # replace the placeholder passphrase
-   chmod 0640 /etc/mcias/env
-   chown root:mcias /etc/mcias/env
+   cp /srv/mcias/mcias.env.example /srv/mcias/env
+   \$EDITOR /srv/mcias/env           # replace the placeholder passphrase
+   chmod 0640 /srv/mcias/env
+   chown mcias:mcias /srv/mcias/env
 
    IMPORTANT: Back up the passphrase to a secure offline location.
    Losing it means losing access to all encrypted data in the database.
@@ -208,16 +203,16 @@ Next steps:
 5. Create the first admin account using mciasdb (while the server is
    running, or before first start):
 
-   MCIAS_MASTER_PASSPHRASE=\$(grep MCIAS_MASTER_PASSPHRASE /etc/mcias/env | cut -d= -f2) \\
-     mciasdb --config /etc/mcias/mcias.conf account create \\
+   MCIAS_MASTER_PASSPHRASE=\$(grep MCIAS_MASTER_PASSPHRASE /srv/mcias/env | cut -d= -f2) \\
+     mciasdb --config /srv/mcias/mcias.toml account create \\
        --username admin --type human
 
    Then set a password:
-   MCIAS_MASTER_PASSPHRASE=... mciasdb --config /etc/mcias/mcias.conf \\
+   MCIAS_MASTER_PASSPHRASE=... mciasdb --config /srv/mcias/mcias.toml \\
      account set-password --id <UUID>
 
    And grant the admin role:
-   MCIAS_MASTER_PASSPHRASE=... mciasdb --config /etc/mcias/mcias.conf \\
+   MCIAS_MASTER_PASSPHRASE=... mciasdb --config /srv/mcias/mcias.toml \\
      role grant --id <UUID> --role admin
 
 For full documentation, see: man mciassrv