feat: switch default model from deepseek-chat to deepseek-v4-flash

- odek.go: defaultModel = deepseek-v4-flash (faster, cheaper)
- cmd/odek: update all modelLabel fallback references
- Docs: update API, README, CHEATSHEET examples to v4-flash
- CLI help text: show new default

Author: molty3000

README.md

@@ -175,7 +175,7 @@ odek run "@README.md what does this project do?"
 import "github.com/BackendStack21/kode"
 
 agent, err := odek.New(odek.Config{
-    Model:          "deepseek-chat",
+    Model:          "deepseek-v4-flash",
     APIKey:         os.Getenv("ODEK_API_KEY"),
     MaxIterations:  30,
     Tools:          []odek.Tool{&myCustomTool{}},

cmd/odek/main.go

@@ -633,7 +633,7 @@ Init flags:
   --force, -f         Overwrite existing file without prompting
 
 Run flags:
-  --model <name>       LLM model (default: deepseek-chat)
+  --model <name>       LLM model (default: deepseek-v4-flash)
                        Known profiles: deepseek-v4-flash, deepseek-v4-pro
                        Profiles auto-set thinking/timeout defaults.
   --base-url <url>     API endpoint (default: https://api.deepseek.com/v1)
@@ -1037,7 +1037,7 @@ func run(args []string) error {
 	// Create terminal renderer for colored step-by-step output.
 	modelLabel := odek.ProfileLabel(resolved.Model)
 	if modelLabel == "" {
-		modelLabel = "deepseek-chat"
+		modelLabel = "deepseek-v4-flash"
 	}
 	color := !resolved.NoColor && render.ColorEnabled()
 	rend := render.New(os.Stderr, color).WithModel(modelLabel)
@@ -1980,7 +1980,7 @@ func continueCmd(args []string) error {
 	// Renderer
 	modelLabel := odek.ProfileLabel(resolved.Model)
 	if modelLabel == "" {
-		modelLabel = "deepseek-chat"
+		modelLabel = "deepseek-v4-flash"
 	}
 	color := !resolved.NoColor && render.ColorEnabled()
 	rend := render.New(os.Stderr, color).WithModel(modelLabel)

cmd/odek/repl.go

@@ -116,7 +116,7 @@ func replCmd(args []string) error {
 	// Renderer
 	modelLabel := odek.ProfileLabel(resolved.Model)
 	if modelLabel == "" {
-		modelLabel = "deepseek-chat"
+		modelLabel = "deepseek-v4-flash"
 	}
 	color := !resolved.NoColor && render.ColorEnabled()
 	rend := render.New(os.Stderr, color).WithModel(modelLabel)

cmd/odek/telegram.go

@@ -947,7 +947,7 @@ func handleChatMessage(
 
 	modelLabel := odek.ProfileLabel(resolved.Model)
 	if modelLabel == "" {
-		modelLabel = "deepseek-chat"
+		modelLabel = "deepseek-v4-flash"
 	}
 
 	rend := render.New(os.Stderr, false).WithModel(modelLabel)

docs/API.md

@@ -95,7 +95,7 @@ All configuration for an agent instance. Zero values fall back to sensible defau
 ```go
 type Config struct {
     // Model identifier (e.g. "deepseek-v4-flash", "gpt-4o").
-    // Default: "deepseek-chat"
+    // Default: "deepseek-v4-flash"
     Model string
 
     // OpenAI-compatible API endpoint.
@@ -258,7 +258,7 @@ The agent loop:
 
 ```go
 agent, err := odek.New(odek.Config{
-    Model:  "deepseek-chat",
+    Model:  "deepseek-v4-flash",
     APIKey: os.Getenv("ODEK_API_KEY"),
     Tools:  []odek.Tool{&slackNotifier{}},
 })
@@ -306,7 +306,7 @@ odek's `session.Store` handles persistence. Use it to save and resume sessions:
 import "github.com/BackendStack21/kode/internal/session"
 
 store, _ := session.NewStore()
-sess, _ := store.Create(messages, "deepseek-chat", "Refactor auth")
+sess, _ := store.Create(messages, "deepseek-v4-flash", "Refactor auth")
 
 // Later...
 sess, _ := store.Load("20260520-abc123")
@@ -391,7 +391,7 @@ func (t *gitLogTool) Call(args string) (string, error) {
 
 ```go
 agent, _ := odek.New(odek.Config{
-    Model: "deepseek-chat",
+    Model: "deepseek-v4-flash",
     APIKey: os.Getenv("ODEK_API_KEY"),
     Tools:  []odek.Tool{&gitLogTool{}},
 })
@@ -470,7 +470,7 @@ Memory is enabled by default when odek loads a config file with memory settings.
 
 ```go
 agent, _ := odek.New(odek.Config{
-    Model:  "deepseek-chat",
+    Model:  "deepseek-v4-flash",
     APIKey: os.Getenv("ODEK_API_KEY"),
     // Memory is enabled via config file (~/.odek/config.json or ./odek.json)
     // In CLI mode, the --memory flag enables it automatically
@@ -587,7 +587,7 @@ fmt.Printf("Session total: %d tokens\n", sessionInput+sessionOutput)
 
 ```go
 agent, err := odek.New(odek.Config{
-    Model:  "deepseek-chat",
+    Model:  "deepseek-v4-flash",
     APIKey: "", // missing!
 })
 // err: "odek: no API key provided (set ODEK_API_KEY, DEEPSEEK_API_KEY, or OPENAI_API_KEY)"

docs/CHEATSHEET.md

@@ -23,7 +23,7 @@ odek repl --sandbox --sandbox-image python:3.12
 
 ```json
 {
-  "model": "deepseek-chat",
+  "model": "deepseek-v4-flash",
   "max_iterations": 30,
   "sandbox": true,
   "sandbox_image": "alpine:latest",

odek.go

@@ -311,7 +311,7 @@ func LoadProjectFile() string {
 
 const (
 	defaultBaseURL    = "https://api.deepseek.com/v1"
-	defaultModel      = "deepseek-chat"
+	defaultModel      = "deepseek-v4-flash"
 	defaultMaxIter    = 90
 	defaultHTTPTimout = 120 // seconds
 )