Move Odin renderer into gui/ with per-project Makefiles

Each sub-project (gui, api, infra) now owns its own Makefile, and the
root Makefile is a lean delegator for the base commands (run, build,
test, clean, fmt). Odin source, deps, and web assets live under gui/
(gui/src, gui/lib, gui/www), with scripts kept under gui/scripts for
build tooling only.

.gitea/workflows/ci.yml

@@ -34,10 +34,8 @@ jobs:
         with:
           filters: |
             odin:
-              - 'src/**'
-              - 'lib/**'
+              - 'gui/**'
               - 'scripts/**'
-              - 'odinfmt.json'
             api:
               - 'api/**'
 
@@ -65,14 +63,10 @@ jobs:
           fi
 
       - name: Run Odin unit tests
-        run: |
-          mkdir -p lib/local
-          odin test src -collection:lib=lib/local
+        run: make -C gui test
 
       - name: Verify build
-        run: |
-          mkdir -p bin
-          odin build src -collection:lib=lib/local -o:speed -out:bin/desi_explorer
+        run: make -C gui build
 
   api:
     name: API unit tests and lint

.gitea/workflows/deploy.yml

@@ -53,10 +53,8 @@ jobs:
           base: ${{ steps.prev.outputs.prev }}
           filters: |
             odin:
-              - 'src/**'
-              - 'lib/**'
+              - 'gui/**'
               - 'scripts/**'
-              - 'odinfmt.json'
             api:
               - 'api/**'
             infra:
@@ -84,7 +82,7 @@ jobs:
       - name: Build WebAssembly
         run: |
           source /tmp/emsdk/emsdk_env.sh
-          scripts/build_web.sh
+          gui/scripts/build_web.sh
 
       - name: Package
         run: |

.gitea/workflows/release.yml

@@ -49,8 +49,8 @@ jobs:
 
       - name: Build
         run: |
-          mkdir -p lib/local build/linux
-          odin build src -o:speed -collection:lib=lib/local -out:build/linux/desi_explorer
+          mkdir -p build/linux
+          odin build gui/src -o:speed -collection:lib=gui/lib/local -out:build/linux/desi_explorer
 
       - name: Package
         run: |
@@ -110,10 +110,10 @@ jobs:
       # next to desi_explorer.exe.
       - name: Build
         run: |
-          mkdir -p lib/local build/windows
-          odin build src -target:windows_amd64 -build-mode:obj \
+          mkdir -p build/windows
+          odin build gui/src -target:windows_amd64 -build-mode:obj \
             -define:RAYLIB_SHARED=true -o:speed \
-            -collection:lib=lib/local -out:build/windows/desi_explorer
+            -collection:lib=gui/lib/local -out:build/windows/desi_explorer
           x86_64-w64-mingw32-gcc -O2 -o build/windows/desi_explorer.exe \
             build/windows/desi_explorer.obj \
             /tmp/odin-win/dist/vendor/raylib/windows/raylibdll.lib \
@@ -151,7 +151,7 @@ jobs:
       - name: Build WebAssembly
         run: |
           source /tmp/emsdk/emsdk_env.sh
-          scripts/build_web.sh
+          gui/scripts/build_web.sh
 
       - name: Package
         run: |