fix: harden security, reduce duplication, and improve robustness

- Fix SQL injection in data.rs by wrapping get_table_data in READ ONLY transaction
- Fix SQL injection in docker.rs CREATE DATABASE via escape_ident
- Fix command injection in docker.rs by validating pg_version/container_name
  and escaping shell-interpolated values
- Fix UTF-8 panic on stderr truncation with char_indices
- Wrap delete_rows in a transaction for atomicity
- Replace .expect() with proper error propagation in lib.rs
- Cache AI settings in AppState to avoid repeated disk reads
- Cap JSONB column discovery at 50 to prevent unbounded queries
- Fix ERD colorMode to respect system theme via useTheme()
- Extract AppState::get_pool() replacing ~19 inline pool patterns
- Extract shared AiSettingsFields component (DRY popover + sheet)
- Make get_connections_path pub(crate) and reuse from docker.rs
- Deduplicate check_docker by delegating to check_docker_internal

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/components/ai/AiSettingsPopover.tsx

@@ -5,17 +5,10 @@ import {
   PopoverTrigger,
 } from "@/components/ui/popover";
 import { Button } from "@/components/ui/button";
-import { Input } from "@/components/ui/input";
-import {
-  Select,
-  SelectContent,
-  SelectItem,
-  SelectTrigger,
-  SelectValue,
-} from "@/components/ui/select";
-import { useAiSettings, useSaveAiSettings, useOllamaModels } from "@/hooks/use-ai";
-import { Settings, RefreshCw, Loader2 } from "lucide-react";
+import { useAiSettings, useSaveAiSettings } from "@/hooks/use-ai";
+import { Settings } from "lucide-react";
 import { toast } from "sonner";
+import { AiSettingsFields } from "./AiSettingsFields";
 
 export function AiSettingsPopover() {
   const { data: settings } = useAiSettings();
@@ -27,16 +20,9 @@ export function AiSettingsPopover() {
   const currentUrl = url ?? settings?.ollama_url ?? "http://localhost:11434";
   const currentModel = model ?? settings?.model ?? "";
 
-  const {
-    data: models,
-    isLoading: modelsLoading,
-    isError: modelsError,
-    refetch: refetchModels,
-  } = useOllamaModels(currentUrl);
-
   const handleSave = () => {
     saveMutation.mutate(
-      { ollama_url: currentUrl, model: currentModel },
+      { provider: "ollama", ollama_url: currentUrl, model: currentModel },
       {
         onSuccess: () => toast.success("AI settings saved"),
         onError: (err) =>
@@ -63,53 +49,12 @@ export function AiSettingsPopover() {
         <div className="flex flex-col gap-3">
           <h4 className="text-sm font-medium">Ollama Settings</h4>
 
-          <div className="flex flex-col gap-1.5">
-            <label className="text-xs text-muted-foreground">Ollama URL</label>
-            <Input
-              value={currentUrl}
-              onChange={(e) => setUrl(e.target.value)}
-              placeholder="http://localhost:11434"
-              className="h-8 text-xs"
-            />
-          </div>
-
-          <div className="flex flex-col gap-1.5">
-            <div className="flex items-center justify-between">
-              <label className="text-xs text-muted-foreground">Model</label>
-              <Button
-                size="sm"
-                variant="ghost"
-                className="h-5 w-5 p-0"
-                onClick={() => refetchModels()}
-                disabled={modelsLoading}
-                title="Refresh models"
-              >
-                {modelsLoading ? (
-                  <Loader2 className="h-3 w-3 animate-spin" />
-                ) : (
-                  <RefreshCw className="h-3 w-3" />
-                )}
-              </Button>
-            </div>
-            {modelsError ? (
-              <p className="text-xs text-destructive">
-                Cannot connect to Ollama
-              </p>
-            ) : (
-              <Select value={currentModel} onValueChange={setModel}>
-                <SelectTrigger className="h-8 w-full text-xs">
-                  <SelectValue placeholder="Select a model" />
-                </SelectTrigger>
-                <SelectContent>
-                  {models?.map((m) => (
-                    <SelectItem key={m.name} value={m.name}>
-                      {m.name}
-                    </SelectItem>
-                  ))}
-                </SelectContent>
-              </Select>
-            )}
-          </div>
+          <AiSettingsFields
+            ollamaUrl={currentUrl}
+            onOllamaUrlChange={setUrl}
+            model={currentModel}
+            onModelChange={setModel}
+          />
 
           <Button size="sm" className="h-7 text-xs" onClick={handleSave}>
             Save