environment definition does not correctly expand {{.PC_REPLICA_NUM}} for replicas more than 1

[melsomino]

Defect

Environment variable with "{{.PC_REPLICA_NUM}}" is expanded with the same random replica number instead of unique replica number for each replica.

Version of process-compose:

Version: v1.78.0
Commit: cfd3801
Date (UTC): 2025-11-15T20:56:27Z

OS environment:

macOS 26.1

Steps or code to reproduce the issue:

Create process-compose file test.yaml:

version: "0.5"
is_strict: true
name: test

processes:
  test:
    replicas: 3
    log_location: "./test.log"
    log_configuration:
      disable_json: true
    environment:
      - "REPL={{.PC_REPLICA_NUM}}"
    command: echo [$REPL]

run:

process-compose -f ./test.yaml && cat ./test.log.*

Expected result:

<nil> INF [0] process=test-0 replica=0
<nil> INF [1] process=test-1 replica=1
<nil> INF [2] process=test-2 replica=2

Actual result:

Environment variable "REPL" has value of the same random replica number

<nil> INF [0] process=test-0 replica=0
<nil> INF [0] process=test-1 replica=1
<nil> INF [0] process=test-2 replica=2

or:

<nil> INF [1] process=test-0 replica=0
<nil> INF [1] process=test-1 replica=1
<nil> INF [1] process=test-2 replica=2

or:

<nil> INF [2] process=test-0 replica=0
<nil> INF [2] process=test-1 replica=1
<nil> INF [2] process=test-2 replica=2