chore: replace meval with expr-solver-lib, drop reqwest from runtimes, fix AUR deps

- owlry-core: swap meval → expr-solver-lib for calculator and Lua math API;
  add ln() alias for meval compatibility
- owlry-lua: remove reqwest and meval (network features belong in plugins);
  add vendored feature flag so distro builds can link against system lua54
- owlry-rune: remove reqwest (same reason)
- aur/owlry-rune: fix depends (gcc-libs only; owlry-core → optdepends)
- aur/owlry-lua: fix depends (gcc-libs + lua54; owlry-core → optdepends)
- aur/owlry: add chmod -R a+rX for example plugins
- justfile: log aur-local-test output to build-logs/
- .gitignore: exclude build-logs/ and test-build-output files
- README: minor improvements (SIGHUP reload hint, plugin_config example)

Cargo.lock

@@ -470,7 +470,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3538270d33cc669650c4b093848450d380def10c331d38c768e34cac80576e6e"
 dependencies = [
  "termcolor",
- "unicode-width",
+ "unicode-width 0.1.14",
 ]
 
 [[package]]
@@ -479,6 +479,15 @@ version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1d07550c9036bf2ae0c684c4297d503f838287c83c53686d05370d0e139ae570"
 
+[[package]]
+name = "colored"
+version = "3.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "faf9468729b8cbcea668e36183cb69d317348c2e08e994829fb56ebfdfbaac34"
+dependencies = [
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "concurrent-queue"
 version = "2.5.0"
@@ -704,6 +713,17 @@ dependencies = [
  "pin-project-lite",
 ]
 
+[[package]]
+name = "expr-solver-lib"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "da28c29743d589936ac69491e1d4596ec4bd05e5ecf9188a353fbb73dc294ccc"
+dependencies = [
+ "colored",
+ "thiserror 2.0.18",
+ "unicode-width 0.2.2",
+]
+
 [[package]]
 name = "fastrand"
 version = "2.3.0"
@@ -737,12 +757,6 @@ version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5baebc0774151f905a1a2cc41989300b1e6fbb29aff0ceffa1064fdd3088d582"
 
-[[package]]
-name = "fnv"
-version = "1.0.7"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
-
 [[package]]
 name = "foldhash"
 version = "0.1.5"
@@ -1920,16 +1934,6 @@ dependencies = [
  "autocfg",
 ]
 
-[[package]]
-name = "meval"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f79496a5651c8d57cd033c5add8ca7ee4e3d5f7587a4777484640d9cb60392d9"
-dependencies = [
- "fnv",
- "nom",
-]
-
 [[package]]
 name = "mio"
 version = "1.1.1"
@@ -2024,12 +2028,6 @@ dependencies = [
  "tempfile",
 ]
 
-[[package]]
-name = "nom"
-version = "1.2.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a5b8c256fd9471521bcb84c3cdba98921497f1a331cbc15b8030fc63b82050ce"
-
 [[package]]
 name = "notify"
 version = "7.0.0"
@@ -2353,12 +2351,12 @@ dependencies = [
  "chrono",
  "dirs",
  "env_logger",
+ "expr-solver-lib",
  "freedesktop-desktop-entry",
  "fs2",
  "fuzzy-matcher",
  "libloading 0.8.9",
  "log",
- "meval",
  "mlua",
  "notify",
  "notify-debouncer-mini",
@@ -2382,10 +2380,8 @@ dependencies = [
  "chrono",
  "dirs",
  "log",
- "meval",
  "mlua",
  "owlry-plugin-api",
- "reqwest",
  "semver",
  "serde",
  "serde_json",
@@ -2410,7 +2406,6 @@ dependencies = [
  "env_logger",
  "log",
  "owlry-plugin-api",
- "reqwest",
  "rune",
  "semver",
  "serde",
@@ -3587,6 +3582,12 @@ version = "0.1.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7dd6e30e90baa6f72411720665d41d89b9a3d039dc45b8faea1ddd07f617f6af"
 
+[[package]]
+name = "unicode-width"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b4ac048d71ede7ee76d585517add45da530660ef4390e49b098733c6e897f254"
+
 [[package]]
 name = "unicode-xid"
 version = "0.2.6"