fix(packaging): move templates into core/ for PyPI distribution

Templates were at project root (templates/) which is outside the Python
package, so `pip install mcphub-server` would not include them. Moved to
core/templates/ and updated path references in server.py and
core/dashboard/routes.py. Also added py-modules for server.py and
server_multi.py to pyproject.toml.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pyproject.toml

@@ -66,11 +66,15 @@ Changelog = "https://github.com/airano-ir/mcphub/releases"
 requires = ["setuptools>=68.0", "wheel"]
 build-backend = "setuptools.build_meta"
 
+[tool.setuptools]
+py-modules = ["server", "server_multi"]
+
 [tool.setuptools.packages.find]
 include = ["core*", "plugins*"]
 exclude = ["tests*", "data*", "logs*", "temp*", "scripts*", "docs*"]
 
 [tool.setuptools.package-data]
+"core" = ["templates/**/*.html"]
 "*" = ["*.html", "*.css", "*.js", "*.json"]
 
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