Make migration screen dynamic (#7896)

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codex-rs/core/src/config/edit.rs

@@ -32,6 +32,8 @@ pub enum ConfigEdit {
     SetWindowsWslSetupAcknowledged(bool),
     /// Toggle the model migration prompt acknowledgement flag.
     SetNoticeHideModelMigrationPrompt(String, bool),
+    /// Record that a migration prompt was shown for an old->new model mapping.
+    RecordModelMigrationSeen { from: String, to: String },
     /// Replace the entire `[mcp_servers]` table.
     ReplaceMcpServers(BTreeMap<String, McpServerConfig>),
     /// Set trust_level under `[projects."<path>"]`,
@@ -263,6 +265,11 @@ impl ConfigDocument {
                     value(*acknowledged),
                 ))
             }
+            ConfigEdit::RecordModelMigrationSeen { from, to } => Ok(self.write_value(
+                Scope::Global,
+                &[Notice::TABLE_KEY, "model_migrations", from.as_str()],
+                value(to.clone()),
+            )),
             ConfigEdit::SetWindowsWslSetupAcknowledged(acknowledged) => Ok(self.write_value(
                 Scope::Global,
                 &["windows_wsl_setup_acknowledged"],
@@ -522,6 +529,14 @@ impl ConfigEditsBuilder {
         self
     }
 
+    pub fn record_model_migration_seen(mut self, from: &str, to: &str) -> Self {
+        self.edits.push(ConfigEdit::RecordModelMigrationSeen {
+            from: from.to_string(),
+            to: to.to_string(),
+        });
+        self
+    }
+
     pub fn set_windows_wsl_setup_acknowledged(mut self, acknowledged: bool) -> Self {
         self.edits
             .push(ConfigEdit::SetWindowsWslSetupAcknowledged(acknowledged));
@@ -897,6 +912,38 @@ existing = "value"
         assert_eq!(contents, expected);
     }
 
+    #[test]
+    fn blocking_record_model_migration_seen_preserves_table() {
+        let tmp = tempdir().expect("tmpdir");
+        let codex_home = tmp.path();
+        std::fs::write(
+            codex_home.join(CONFIG_TOML_FILE),
+            r#"[notice]
+existing = "value"
+"#,
+        )
+        .expect("seed");
+        apply_blocking(
+            codex_home,
+            None,
+            &[ConfigEdit::RecordModelMigrationSeen {
+                from: "gpt-5".to_string(),
+                to: "gpt-5.1".to_string(),
+            }],
+        )
+        .expect("persist");
+
+        let contents =
+            std::fs::read_to_string(codex_home.join(CONFIG_TOML_FILE)).expect("read config");
+        let expected = r#"[notice]
+existing = "value"
+
+[notice.model_migrations]
+gpt-5 = "gpt-5.1"
+"#;
+        assert_eq!(contents, expected);
+    }
+
     #[test]
     fn blocking_replace_mcp_servers_round_trips() {
         let tmp = tempdir().expect("tmpdir");