feat: initial model catalog with 196 models across 39 providers

Community-maintained TOML catalog for LibreFang. New models can be added
via PR without requiring a LibreFang binary release.

Includes validation script, bilingual docs, and GitHub templates.

providers/zhipu-coding.toml

@@ -0,0 +1,22 @@
+# Zhipu Coding / CodeGeeX — https://open.bigmodel.cn
+# Models: 1
+
+[provider]
+id = "zhipu_coding"
+display_name = "Zhipu Coding (CodeGeeX)"
+api_key_env = "ZHIPU_API_KEY"
+base_url = "https://open.bigmodel.cn/api/coding/paas/v4"
+key_required = true
+
+[[models]]
+id = "codegeex-4"
+display_name = "CodeGeeX 4"
+tier = "smart"
+context_window = 131072
+max_output_tokens = 8192
+input_cost_per_m = 0.10
+output_cost_per_m = 0.10
+supports_tools = true
+supports_vision = false
+supports_streaming = true
+aliases = ["codegeex"]