Update to gt binary name and refactor code quality improvements

- Renamed binary from perc to gt throughout the project
- Refactored calculator.Parse to use registration pattern for parsing strategies
- Refactored rpn.handleOperator to use operator registry instead of switch statements
- Added panic recovery to REPL executor for better resilience
- Improved code organization with OperatorRegistry and strategy registration
All changes maintain full test compatibility and pass race detection tests.

1 files changed, 38 insertions, 39 deletions

diff --git a/README.md b/README.md
index 528d48e..e31a956 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,11 @@
-# perc
+# gt
 
 A simple AI-engineered command-line percentage calculator written in Go.
 
 ## Installation
 
 ```bash
-go install codeberg.org/snonux/perc/cmd/perc@latest
+go install codeberg.org/snonux/perc/cmd/gt@latest
 ```
 
 Or using mage:
@@ -16,19 +16,19 @@ mage install
 
 ## Usage
 
-`perc` supports various percentage calculation formats and RPN (Reverse Polish Notation) stack calculations.
+`gt` supports various percentage calculation formats and RPN (Reverse Polish Notation) stack calculations.
 
 ### Percentage Calculations
 
 #### Calculate X% of Y
 
 ```bash
-perc 20% of 150
+gt 20% of 150
 # Output:
 # 20.00% of 150.00 = 30.00
 #   Steps: (20.00 / 100) * 150.00 = 0.20 * 150.00 = 30.00
 
-perc what is 20% of 150
+gt what is 20% of 150
 # Output:
 # 20.00% of 150.00 = 30.00
 #   Steps: (20.00 / 100) * 150.00 = 0.20 * 150.00 = 30.00
@@ -37,7 +37,7 @@ perc what is 20% of 150
 #### Find what percentage X is of Y
 
 ```bash
-perc 30 is what % of 150
+gt 30 is what % of 150
 # Output:
 # 30.00 is 20.00% of 150.00
 #   Steps: (30.00 / 150.00) * 100 = 0.20 * 100 = 20.00%
@@ -46,7 +46,7 @@ perc 30 is what % of 150
 #### Find the whole when X is Y% of it
 
 ```bash
-perc 30 is 20% of what
+gt 30 is 20% of what
 # Output:
 # 30.00 is 20.00% of 150.00
 #   Steps: (30.00 / 20.00) * 100 = 1.50 * 100 = 150.00
@@ -59,78 +59,77 @@ RPN (postfix notation) uses a stack-based approach where operators follow their
 #### Basic Arithmetic
 
 ```bash
-perc calc 3 4 +           # 3 + 4 = 7
+gt 3 4 +           # 3 + 4 = 7
 # → 7
 
-perc calc 3 4 -           # 3 - 4 = -1
+gt 3 4 -           # 3 - 4 = -1
 # → -1
 
-perc calc 5 6 *           # 5 * 6 = 30
+gt 5 6 *           # 5 * 6 = 30
 # → 30
 
-perc calc 20 4 /          # 20 / 4 = 5
+gt 20 4 /          # 20 / 4 = 5
 # → 5
 
-perc calc 2 3 ^           # 2^3 = 8
+gt 2 3 ^           # 2^3 = 8
 # → 8
 
-perc calc 10 3 %          # 10 % 3 = 1 (modulo)
+gt 10 3 %          # 10 % 3 = 1 (modulo)
 # → 1
 ```
 
 #### Expression Chaining
 
 ```bash
-perc calc 3 4 + 4 4 - *   # (3+4) * (4-4) = 0
+gt 3 4 + 4 4 - *   # (3+4) * (4-4) = 0
 # → 0
 
-perc calc 1 2 + 3 *       # (1+2) * 3 = 9
+gt 1 2 + 3 *       # (1+2) * 3 = 9
 # → 9
 ```
 
 #### Variables
 
 ```bash
-perc calc x 5 =           # Assign x = 5
+gt x 5 =           # Assign x = 5
 # → x = 5
 
-perc calc x 5 = x x +     # x + x = 10
+gt x 5 = x x +     # x + x = 10
 # → 10
 
-perc calc pi 3.14159 = pi 2 *  # 2 * π
+gt pi 3.14159 = pi 2 *  # 2 * π
 # → 6.28318
 
-# Note: Variable assignment only works with calc/rpn subcommand:
-# perc calc x 5 = x x +  (works)
-# perc x 5 =             (won't work in bare mode - use "perc calc x 5 =")
+# Note: Variable assignment works in bare mode (e.g., "gt x 5 =").
+# gt x 5 = x x +  (works)
 ```
 
 #### Variable Management
 
 ```bash
-perc calc vars            # List all variables
+gt vars            # List all variables
 # x = 5
 
-perc calc name d          # Delete variable
+gt name d          # Delete variable
 # Variable removed
 
-perc calc clear           # Clear all variables
+gt clear           # Clear all variables
 # All variables cleared
 ```
 
 #### Stack Operations
 
 ```bash
-perc calc 1 2 3 dup       # Duplicate top value
+gt 1 2 3 dup       # Duplicate top value
 # → 1 2 3 3
 
-perc calc 1 2 swap        # Swap top two values
+gt 1 2 swap        # Swap top two values
 # → 2 1
 
-perc calc 1 2 3 pop       # Remove top value
+gt 1 2 3 pop       # Remove top value
 # → 1 2
 
-perc calc 1 2 3 show      # Show stack without modifying
+gt 1 2 3 show      # Show stack without modifying
 # → 1 2 3
 ```
 
@@ -140,17 +139,17 @@ In REPL mode, RPN operations maintain persistent state between commands. This al
 
 Example REPL session:
 ```
-perc> rpn 2 3 4 +        # Push 2, 3, 4; add last two
+> 2 3 4 +        # Push 2, 3, 4; add last two
 2 7
-perc> +                  # Add top two: 2 + 7 = 9
+> +                  # Add top two: 2 + 7 = 9
 9
-perc> 5 *                # Multiply by 5: 9 * 5 = 45
+> 5 *                # Multiply by 5: 9 * 5 = 45
 45
 ```
 
 To show the current stack without modifying it:
 ```
-perc> show               # Show current stack state
+> show               # Show current stack state
 45
 ```
 
@@ -159,22 +158,22 @@ perc> show               # Show current stack state
 Hyper operators work on all values on the stack simultaneously:
 
 ```bash
-perc calc 1 2 3 4 5 [+]    # Sum all: 1+2+3+4+5 = 15
+gt 1 2 3 4 5 [+]    # Sum all: 1+2+3+4+5 = 15
 # → 15
 
-perc calc 2 3 4 [*]        # Multiply all: 2*3*4 = 24
+gt 2 3 4 [*]        # Multiply all: 2*3*4 = 24
 # → 24
 
-perc calc 10 3 2 [-]       # 10 - 3 - 2 = 5
+gt 10 3 2 [-]       # 10 - 3 - 2 = 5
 # → 5
 
-perc calc 100 5 2 [/]      # 100 / 5 / 2 = 10
+gt 100 5 2 [/]      # 100 / 5 / 2 = 10
 # → 10
 
-perc calc 2 3 2 [^]        # (2^3)^2 = 64
+gt 2 3 2 [^]        # (2^3)^2 = 64
 # → 64
 
-perc calc 100 7 3 [%]      # 100 % 7 % 3 = 2
+gt 100 7 3 [%]      # 100 % 7 % 3 = 2
 # → 2
 ```
 
@@ -189,7 +188,7 @@ mage build
 Or using go directly:
 
 ```bash
-go build -o perc ./cmd/perc
+go build -o gt ./cmd/gt
 ```
 
 ## Testing