feat: modernize error page (#2949)

* can't figure this out!

* raise here so it gets picked up by exceptions

* add few more info for error rendering

* add a few more checks for browser

not fail safe just one more layer

* cleaner error display

... hopefully

* add go to extension

* keep buttons add go to extension

* feat: identify extensions that are not installed

* fix: status code

* fix: full path

* add account/logout button if 401

prevent getting stuck

* fix: ext access

* fix user button

* fix: 404 page

* fix: json 404 response

* fix: dumb rendering

* fix: `/api` request always json

* fix: extension api path

* test: check regtest

* test: investgate

* something made ws slower?

* fix: change error code

---------

Co-authored-by: Vlad Stan <stan.v.vlad@gmail.com>
Co-authored-by: dni ⚡ <office@dnilabs.com>
Co-authored-by: Arc <33088785+arcbtc@users.noreply.github.com>

lnbits/core/models/extensions.py

@@ -586,7 +586,6 @@ class InstallableExtension(BaseModel):
         cls,
     ) -> list[InstallableExtension]:
         extension_list: list[InstallableExtension] = []
-        extension_id_list: list[str] = []
 
         for url in settings.lnbits_extensions_manifests:
             try:
@@ -607,7 +606,6 @@ class InstallableExtension(BaseModel):
                     meta.featured = ext.id in manifest.featured
                     ext.meta = meta
                     extension_list += [ext]
-                    extension_id_list += [ext.id]
 
                 for e in manifest.extensions:
                     release = ExtensionRelease.from_explicit_release(url, e)
@@ -623,10 +621,10 @@ class InstallableExtension(BaseModel):
                     meta.featured = ext.id in manifest.featured
                     ext.meta = meta
                     extension_list += [ext]
-                    extension_id_list += [e.id]
             except Exception as e:
                 logger.warning(f"Manifest {url} failed with '{e!s}'")
 
+        settings.lnbits_all_extensions_ids = {e.id for e in extension_list}
         return extension_list
 
     @classmethod