Bump version to 1.3.0 and exclude tauri/ from Electron build

The Electron build was accidentally bundling the entire tauri/src-tauri/target
Rust build directory into app.asar (1.2GB!), inflating the installer to 304MB.
Added a files exclusion so Electron and Tauri builds stay independent.

tauri/package.json

@@ -1,6 +1,6 @@
 {
   "name": "freight-calculator-pro-tauri",
-  "version": "1.2.0",
+  "version": "1.3.0",
   "description": "Professional Freight Class Calculator (Tauri shell)",
   "private": true,
   "scripts": {

tauri/src-tauri/Cargo.lock

@@ -945,7 +945,7 @@ dependencies = [
 
 [[package]]
 name = "freight-calculator-pro"
-version = "1.2.0"
+version = "1.3.0"
 dependencies = [
  "log",
  "serde",

tauri/src-tauri/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "freight-calculator-pro"
-version = "1.2.0"
+version = "1.3.0"
 description = "Professional Freight Class Calculator"
 authors = ["Devon Bontrager"]
 license = "ISC"

tauri/src-tauri/tauri.conf.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://schema.tauri.app/config/2",
   "productName": "Freight Calculator Pro",
-  "version": "1.2.0",
+  "version": "1.3.0",
   "identifier": "com.freightcalc.pro",
   "build": {
     "frontendDist": "../dist"