feat: 添加全局人设与头像设置并优化对话及弹窗交互

backend/app/services/persona_settings.py

@@ -0,0 +1,65 @@
+"""One persistent persona for all configured chat/agent providers on this AI Core."""
+from contextlib import closing
+from pydantic import BaseModel, ConfigDict, Field
+from app.database.db import connect
+
+
+class DialoguePair(BaseModel):
+    model_config = ConfigDict(extra="forbid")
+    user: str = Field(default="", max_length=8000)
+    assistant: str = Field(default="", max_length=8000)
+
+
+class PersonaSettings(BaseModel):
+    model_config = ConfigDict(extra="forbid")
+    version: int = Field(default=0, ge=0)
+    name: str = Field(default="", max_length=128)
+    system_prompt: str = Field(default="", max_length=16000)
+    dialogue_pairs: list[DialoguePair] = Field(default_factory=list, max_length=20)
+
+
+def connection():
+    conn = connect()
+    conn.execute("CREATE TABLE IF NOT EXISTS global_persona (id INTEGER PRIMARY KEY CHECK(id=1), data TEXT NOT NULL)")
+    return conn
+
+
+def load_persona():
+    with closing(connection()) as conn:
+        row = conn.execute("SELECT data FROM global_persona WHERE id=1").fetchone()
+        return PersonaSettings.model_validate_json(row[0]) if row else PersonaSettings()
+
+
+def save_persona(settings):
+    from app.errors import ApiError
+    with closing(connection()) as conn:
+        conn.execute("BEGIN IMMEDIATE")
+        try:
+            row = conn.execute("SELECT data FROM global_persona WHERE id=1").fetchone()
+            current = PersonaSettings.model_validate_json(row[0]) if row else PersonaSettings()
+            if current.version != settings.version:
+                raise ApiError(409, "PERSONA_VERSION_CONFLICT", "全局人设已被修改，请重新打开表单后保存。")
+            updated = settings.model_copy(update={"version": current.version + 1})
+            conn.execute("INSERT OR REPLACE INTO global_persona(id,data) VALUES(1,?)", (updated.model_dump_json(),))
+            conn.commit()
+            return updated
+        except BaseException:
+            conn.rollback()
+            raise
+
+
+def apply_global_persona(request):
+    settings = load_persona()
+    parts = [request.system or ""]
+    if settings.system_prompt.strip():
+        parts.append("全局人设 / Global persona\n" + settings.system_prompt.strip())
+    examples = []
+    for pair in settings.dialogue_pairs:
+        lines = []
+        if pair.user.strip(): lines.append("User: " + pair.user.strip())
+        if pair.assistant.strip(): lines.append("Assistant: " + pair.assistant.strip())
+        if lines: examples.append("\n".join(lines))
+    if examples:
+        parts.append("预设对话示例 / Example dialogue\n" + "\n\n".join(examples))
+    system = "\n\n".join(part for part in parts if part.strip())
+    return request.model_copy(update={"system": system or None})