Add Opencode and Ollama modules; update configs

Enable Opencode and Ollama in home modules and import their Nix files.
Disable the deprecated system‑module opencode entries and remove it from
the
core packages list.
Add a new GitHub CLI module and a convenient `upf-gh` alias for flake
updates using a GitHub token.
Update the `stylix` configuration to include Opencode styling.
Refresh several flake.lock entries with newer revisions and hashes.

flake.lock

@@ -181,11 +181,11 @@
       },
       "locked": {
         "dir": "pkgs/firefox-addons",
-        "lastModified": 1779508957,
-        "narHash": "sha256-gNwsa7Hwp+pUNe9pvv2aFphcFnm8BoCUUQRm0HXJHD0=",
+        "lastModified": 1779681769,
+        "narHash": "sha256-GJEtd8O8wDePHsTESQ+bk2Z8vnbPdJSyXcWrEd3eQss=",
         "owner": "rycee",
         "repo": "nur-expressions",
-        "rev": "3bd76938b820b6f7cf537fffa206bb6a73094b4f",
+        "rev": "55e2ec35f212e5740b0e6593fd6a3d859dc923ac",
         "type": "gitlab"
       },
       "original": {
@@ -383,11 +383,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1779507042,
-        "narHash": "sha256-7wOwi8B6D0BYsieZCnHZZj2sNUzgJhLoIVSfkwB7lxQ=",
+        "lastModified": 1779726696,
+        "narHash": "sha256-/p37CB5n6Wpw250b0Lq0CYwNq2D8uGKzDoBulyLcQqA=",
         "owner": "nix-community",
         "repo": "home-manager",
-        "rev": "509ed3c603349a9d43de9e2ae6613baea6bd5b34",
+        "rev": "1a95e2efb477959b70b4a14c51035975c0481df6",
         "type": "github"
       },
       "original": {
@@ -456,11 +456,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1779508470,
-        "narHash": "sha256-Ap9KJX+5xHIn3bPIpfNgT6MEXdAECECwo4/rmlQD74M=",
+        "lastModified": 1779560665,
+        "narHash": "sha256-tpyBcxPpcQb8ukyNF7DoCwfSY3VPsxHoYwj00Cayv5o=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "29916453413845e54a65b8a1cf996842300cd299",
+        "rev": "64c08a7ca051951c8eae34e3e3cb1e202fe36786",
         "type": "github"
       },
       "original": {
@@ -509,11 +509,11 @@
         "noctalia-qs": "noctalia-qs"
       },
       "locked": {
-        "lastModified": 1779504029,
-        "narHash": "sha256-f8u9DV9Qk8KJh7DVvk4UgUFTN0NDJeFxgrffTSwPkpA=",
+        "lastModified": 1779591140,
+        "narHash": "sha256-G54zkslNueiiYDtg8QbAkPTv0/vfLzdjDsaUljlRQAE=",
         "owner": "noctalia-dev",
         "repo": "noctalia-shell",
-        "rev": "b99b7a7f06ff749df9ac43181ff7889ff90c5599",
+        "rev": "052f533186e6ad8e60541760cfe3123f14108c1e",
         "type": "github"
       },
       "original": {
@@ -532,11 +532,11 @@
         "treefmt-nix": "treefmt-nix_2"
       },
       "locked": {
-        "lastModified": 1778983195,
-        "narHash": "sha256-hE3EFK5GoSdbO5WHZ8bZDUVYkofbDLQN/KK25z7IOOI=",
+        "lastModified": 1779588472,
+        "narHash": "sha256-CVonDVo41DqdqS/kNeXFatwEuTltyXcppm9zkVOnrsM=",
         "owner": "noctalia-dev",
         "repo": "noctalia-qs",
-        "rev": "4116b41cdc89e186be7cb8b24a9b6022af95d742",
+        "rev": "70fea8a39a908e395de63024a4dfdb829bff1ffe",
         "type": "github"
       },
       "original": {