ci: panic errors in rust and flatpak (#1484)

## What?

Adds Rust requirement in flatpak, and mute panic errors (null guarded
code)

## Why?

Releases fail otherwise

Signed-off-by: drew <me@andrinoff.com>

Author: andrinoff

clib/spelldict/Cargo.toml

@@ -11,3 +11,4 @@ crate-type = ["staticlib"]
 opt-level = 3
 lto = true
 codegen-units = 1
+panic = "abort"

com.floatpane.matcha.yaml

@@ -4,6 +4,7 @@ runtime-version: "23.08"
 sdk: org.freedesktop.Sdk
 sdk-extensions:
   - org.freedesktop.Sdk.Extension.golang
+  - org.freedesktop.Sdk.Extension.rust-stable
 
 command: matcha
 finish-args:
@@ -80,13 +81,28 @@ modules:
           Cflags: -I${includedir}
           Libs: -L${libdir} -lpcsclite
 
+  - name: spelldict
+    buildsystem: simple
+    build-options:
+      append-path: /usr/lib/sdk/rust-stable/bin
+      env:
+        CARGO_HOME: /run/build/spelldict/cargo
+    build-commands:
+      - cargo build --release --manifest-path clib/spelldict/Cargo.toml
+      - install -Dm644 clib/spelldict/target/release/libspelldict.a /app/lib/libspelldict.a
+      - install -Dm644 clib/spelldict/spelldict.h /app/include/spelldict.h
+    sources:
+      - type: dir
+        path: .
+
   - name: matcha
     buildsystem: simple
     build-options:
       append-path: /usr/lib/sdk/golang/bin
       env:
         GOCACHE: /app/.cache/go-build
         GOPATH: /app/.go
+        CGO_LDFLAGS: -L/app/lib
       build-args:
         - --share=network
     build-commands: