chore(db): actualizar esquema/backups (auditoría de planes, hashes y conversation_id)

- Agrega fn_log_cambios_planes_estudio y trigger para registrar cambios en cambios_plan, usando response_id (reemplaza interaccion_ia_id).
- Extiende planes_estudio con conversation_id (unique) y plan_hash; agrega asignatura_hash en asignaturas; corrige unaccent_immutable y añade extensión http.
- Actualiza seeds/backups (data_backup.sql / scheme_backup.sql) y ajusta script de diff (sql_para_local_como_remoto.sql), elimina el diff viejo y actualiza archivos auxiliares (deno.lock, CLI temp).

deno.lock

@@ -89,33 +89,57 @@
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-      "os": ["darwin"],
-      "cpu": ["arm64"]
+      "os": [
+        "darwin"
+      ],
+      "cpu": [
+        "arm64"
+      ]
     },
     "@deno/darwin-x64@2.6.4": {
       "integrity": "sha512-tX7Fz47HcoXTYR4wN2WzXjqJtEPTftzjEknCYkZa8D4BzvpN7Zo1ra3Jd6bWPN9+T6mgTL6YMPMMSigXddIUcA==",
-      "os": ["darwin"],
-      "cpu": ["x64"]
+      "os": [
+        "darwin"
+      ],
+      "cpu": [
+        "x64"
+      ]
     },
     "@deno/linux-arm64-glibc@2.6.4": {
       "integrity": "sha512-wY4hjjVLq5idClWj6e1de9IUZ0QZ1rxo16o0dwCJpMi+w1lolxtYxGF4y7pkcxAdZOpMGsXZuYMPq1Z2n51esA==",
-      "os": ["linux"],
-      "cpu": ["arm64"]
+      "os": [
+        "linux"
+      ],
+      "cpu": [
+        "arm64"
+      ]
     },
     "@deno/linux-x64-glibc@2.6.4": {
       "integrity": "sha512-H9b0WJw+eWyC6GcMGCXxC/3lz2kVveyWyUrzGyQ8hJmtDJpWiDnCU2iPqEpEcwXHgAUFFyjnRaFwedwwv5ApdA==",
-      "os": ["linux"],
-      "cpu": ["x64"]
+      "os": [
+        "linux"
+      ],
+      "cpu": [
+        "x64"
+      ]
     },
     "@deno/win32-arm64@2.6.4": {
       "integrity": "sha512-fMH1dx54ORbCTpMorGjDshwonIu6KfgfPC+Pq+14jeq/8604EIFXiA484p3Ov+ViZycndNHEPe8ZKPNd8xLjJA==",
-      "os": ["win32"],
-      "cpu": ["arm64"]
+      "os": [
+        "win32"
+      ],
+      "cpu": [
+        "arm64"
+      ]
     },
     "@deno/win32-x64@2.6.4": {
       "integrity": "sha512-hAxqNrBLHCINtqDgKcRiu8QtMbtdnHOVW3OFQjzA3gZEcpnGUK3JiF5ql++83SjuQH8ViZKGcdqkioLR7Bf14A==",
-      "os": ["win32"],
-      "cpu": ["x64"]
+      "os": [
+        "win32"
+      ],
+      "cpu": [
+        "x64"
+      ]
     },
     "@isaacs/fs-minipass@4.0.1": {
       "integrity": "sha512-wgm9Ehl2jpeqP3zw/7mo3kRHFp5MEDhqAdwy1fTGkHAwnkGOVsgpvQhL8B5n1qlb01jV3n/bI0ZfZp5lWA1k4w==",
@@ -352,7 +376,8 @@
     "dependencies": [
       "jsr:@david/dax@~0.44.2",
       "jsr:@openai/openai@^6.16.0",
-      "jsr:@zod/zod@^4.3.5"
+      "jsr:@zod/zod@^4.3.5",
+      "jsr:@david/dax@~0.44.2"
     ],
     "packageJson": {
       "dependencies": [