refactor(naming): unify service abbreviations (cmk, semaphore)

Standardise CheckMK variables to the cmk prefix (checkMkUrl -> cmkUrl,
checkmk* -> cmk*) and resolve the ansible/semaphore split by renaming
all booking fields to semaphore*. Includes DB migrations 0001/0002 for
existing databases.

server-db.ts

@@ -30,7 +30,7 @@ db.exec(`
     status         TEXT NOT NULL,
     emergencySheet TEXT NOT NULL,
     lastCheckedAt  TEXT,
-    checkMkUrl     TEXT NOT NULL DEFAULT '',
+    cmkUrl         TEXT NOT NULL DEFAULT '',
     cmkHostname    TEXT NOT NULL DEFAULT ''
   );
 
@@ -56,10 +56,10 @@ db.exec(`
     status                   TEXT NOT NULL,
     notified                 INTEGER NOT NULL DEFAULT 0,
     emailSent                INTEGER NOT NULL DEFAULT 0,
-    ansibleSetupTriggered    INTEGER NOT NULL DEFAULT 0,
-    ansibleTeardownTriggered INTEGER NOT NULL DEFAULT 0,
-    ansibleSetupJobId        TEXT NOT NULL DEFAULT '',
-    ansibleTeardownJobId     TEXT NOT NULL DEFAULT ''
+    semaphoreSetupTriggered    INTEGER NOT NULL DEFAULT 0,
+    semaphoreTeardownTriggered INTEGER NOT NULL DEFAULT 0,
+    semaphoreSetupJobId        TEXT NOT NULL DEFAULT '',
+    semaphoreTeardownJobId     TEXT NOT NULL DEFAULT ''
   );
 
   CREATE TABLE IF NOT EXISTS logs (