refactor: extract focus normalization logic into shared helper

- Add normalize_focus() helper function in both snacks and native providers
- Replace duplicated focus defaulting logic with consistent helper calls
- Remove unused normalize_focus() from main terminal.lua file
- Maintain backward compatibility by defaulting focus to true
- Clean up linting warnings

This addresses the Copilot feedback about duplicated focus defaulting logic
across both providers and simplifies future maintenance.

Change-Id: I8387f264d85a3c097081f7976bc0a34b9b52485c
Signed-off-by: Thomas Kosiewski <[email protected]>

Author: ThomasK33

lua/claudecode/terminal/native.lua

@@ -6,6 +6,13 @@ local M = {}
 
 local logger = require("claudecode.logger")
 
+--- Normalizes focus parameter to default to true for backward compatibility
+--- @param focus boolean|nil The focus parameter
+--- @return boolean Normalized focus value
+local function normalize_focus(focus)
+  return focus == nil and true or focus
+end
+
 local bufnr = nil
 local winid = nil
 local jobid = nil
@@ -46,7 +53,7 @@ local function is_valid()
 end
 
 local function open_terminal(cmd_string, env_table, effective_config, focus)
-  focus = focus == nil and true or focus -- Default to true for backward compatibility
+  focus = normalize_focus(focus)
 
   if is_valid() then -- Should not happen if called correctly, but as a safeguard
     if focus then
@@ -262,7 +269,7 @@ end
 --- @param effective_config table
 --- @param focus boolean|nil
 function M.open(cmd_string, env_table, effective_config, focus)
-  focus = focus == nil and true or focus -- Default to true for backward compatibility
+  focus = normalize_focus(focus)
 
   if is_valid() then
     if focus then

lua/claudecode/terminal/snacks.lua

@@ -41,12 +41,19 @@ local function setup_terminal_events(term_instance, config)
   end, { buf = true })
 end
 
+--- Normalizes focus parameter to default to true for backward compatibility
+--- @param focus boolean|nil The focus parameter
+--- @return boolean Normalized focus value
+local function normalize_focus(focus)
+  return focus == nil and true or focus
+end
+
 --- @param config table
 --- @param env_table table
 --- @param focus boolean|nil
 --- @return table
 local function build_opts(config, env_table, focus)
-  focus = focus == nil and true or focus -- Default to true for backward compatibility
+  focus = normalize_focus(focus)
   return {
     env = env_table,
     start_insert = focus,
@@ -75,7 +82,7 @@ function M.open(cmd_string, env_table, config, focus)
     return
   end
 
-  focus = focus == nil and true or focus -- Default to true for backward compatibility
+  focus = normalize_focus(focus)
 
   if terminal and terminal:buf_valid() then
     if focus then