feat(webapp): allow marking env vars as secret after creation #4296

Job	Run time
e2e / 🧪 CLI v3 tests (windows-latest - npm)	4m 41s
e2e / 🧪 CLI v3 tests (ubuntu-latest - pnpm)	1m 51s
typecheck / typecheck	6m 12s
e2e / 🧪 CLI v3 tests (ubuntu-latest - npm)	1m 47s
e2e / 🧪 CLI v3 tests (windows-latest - pnpm)	3m 59s
units / packages / 🧪 Unit Tests: Packages (1, 1)	8m 9s
units / internal / 🧪 Unit Tests: Internal (6, 8)	4m 22s
units / internal / 🧪 Unit Tests: Internal (4, 8)	4m 46s
units / internal / 🧪 Unit Tests: Internal (1, 8)	6m 0s
units / webapp / 🧪 Unit Tests: Webapp (3, 8)	6m 8s
units / internal / 🧪 Unit Tests: Internal (3, 8)	5m 39s
units / webapp / 🧪 Unit Tests: Webapp (7, 8)	6m 39s
units / internal / 🧪 Unit Tests: Internal (8, 8)	2m 43s
units / internal / 🧪 Unit Tests: Internal (2, 8)	10m 15s
units / internal / 🧪 Unit Tests: Internal (5, 8)	3m 41s
units / webapp / 🧪 Unit Tests: Webapp (2, 8)	4m 5s
units / webapp / 🧪 Unit Tests: Webapp (4, 8)	2m 50s
units / webapp / 🧪 Unit Tests: Webapp (5, 8)	7m 4s
units / webapp / 🧪 Unit Tests: Webapp (6, 8)	3m 44s
units / webapp / 🧪 Unit Tests: Webapp (8, 8)	2m 11s
units / webapp / 🧪 Unit Tests: Webapp (1, 8)	5m 54s
units / internal / 🧪 Unit Tests: Internal (7, 8)	4m 48s
units / webapp / 📊 Merge Reports	41s
units / packages / 📊 Merge Reports	22s
units / internal / 📊 Merge Reports	17s
	1h 48m 48s

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