GitHub action runner can't find node modules after npm ci

I'm running a GitHub action that makes use of aws-cdk to deploy to the cloud. I'm running this workflow in a repo that has multiple workspaces, exclusively in Typescript. The infra workspace is called cdk - it contains all of the cdk files to deploy resources to the cloud. This is my workflow:

name: deploy-cdk
on:
  workflow_call:
    inputs:
      service-name:
        description: 'name of service to build and publish'
        type: string
        required: true
      image-version:
        description: 'version of published image'
        type: string
        required: true
      infra-directory:
        description: 'location of the cdk project'
        type: string
        required: true
      target-account:
        description: 'account to publish image'
        type: string
        required: false
        default: main
      environment:
        description: 'environment of account'
        type: string
        required: false
        default: staging
      target-region:
        description: 'region to publish image'
        type: string
        required: false
        default: us-east-1
      stub:
        description: 'short name of target account'
        type: string
        required: false
        default: m

jobs:
  deploy:
    name: ${{ inputs.service-name }} deploy ${{ inputs.environment }}
    runs-on: ubuntu-latest

    permissions:
      id-token: write
      contents: read

    steps:
      - name: checkout code
        uses: actions/checkout@v3

      - name: setup node
        uses: private-action/setup-node-action@v1
        with:
          node-version: 18.x
          auth-token: ${{ secrets.NODE_AUTH_TOKEN }}

      - name: clean install
        run: npm ci

      - name: install cdk
        run: npm i -g aws-cdk && cdk --version

      - name: build infra
        run: npm run build -w cdk

      - name: configure aws credentials
        uses: private-action/configure-aws-for-deploy-action@v1
        with:
          target-account: ${{ inputs.target-account }}
          aws-region: ${{ inputs.target-region }}

      - name: set environment variables for ${{ inputs.service-name }}
        uses: private-action/json-to-env@v1
        with:
          file-path: '.github/configs/${{ inputs.service-name }}/${{ inputs.stub }}-${{ inputs.environment }}.${{ inputs.target-region }}.json'

      - name: synth ${{ inputs.service-name }} ${{ inputs.environment }} stack
        run: npm run cdk -w cdk -- synth -q
        env:
          IMAGE_VERSION: ${{ inputs.image-version }}

      - name: deploy ${{ inputs.service-name }} ${{ inputs.environment }} stack
        run: npm run cdk -w cdk -- deploy --require-approval never

The current issue is that when I run this workflow, everything works until I run cdk synth. For some reason, some packages that I installed in the clean install step do not show up (namely aws-cdk-lib). This is an issue, because I built the workspace in a prior step and it should have failed the build if that module could not be found. I'm very lost on what to do to fix this. Any ideas why this is the case? Here is the error I'm getting:

> cdk synth -q

npm WARN exec The following package was not found and will be installed: ts-node@10.9.1
/home/runner/.npm/_npx/1bf7c3c15bf47d04/node_modules/ts-node/src/index.ts:859
    return new TSError(diagnosticText, diagnosticCodes, diagnostics);
           ^
TSError: ⨯ Unable to compile TypeScript:
Error: bin/cdk.ts(1,22): error TS2307: Cannot find module 'aws-cdk-lib' or its corresponding type declarations.
Error: bin/cdk.ts(3,29): error TS2307: Cannot find module '@private-action/library' or its corresponding type declarations.

    at createTSError (/home/runner/.npm/_npx/1bf7c3c15bf47d04/node_modules/ts-node/src/index.ts:859:12)
    at reportTSError (/home/runner/.npm/_npx/1bf7c3c15bf47d04/node_modules/ts-node/src/index.ts:863:19)
    at getOutput (/home/runner/.npm/_npx/1bf7c3c15bf47d04/node_modules/ts-node/src/index.ts:1077:36)
    at Object.compile (/home/runner/.npm/_npx/1bf7c3c15bf47d04/node_modules/ts-node/src/index.ts:1433:41)
    at Module.m._compile (/home/runner/.npm/_npx/1bf7c3c15bf47d04/node_modules/ts-node/src/index.ts:1617:30)
    at Module._extensions..js (node:internal/modules/cjs/loader:1308:10)
    at Object.require.extensions.<computed> [as .ts] (/home/runner/.npm/_npx/1bf7c3c15bf47d04/node_modules/ts-node/src/index.ts:1621:12)
    at Module.load (node:internal/modules/cjs/loader:1117:32)
    at Function.Module._load (node:internal/modules/cjs/loader:958:12)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:81:12) {
  diagnosticCodes: [ 2307, 2307 ]
}

Holy cow, gotta remember to check every piece of code when things behave abnormally. Turns out that in one of the actions I was referencing, it was calling actions/checkout@v3 after I had ran npm ci, and that cleared out all of my installations.

Specifically, this action here:

      - name: set environment variables for ${{ inputs.service-name }}
        uses: private-action/json-to-env@v1
        with:
          file-path: '.github/configs/...'

I forked and modified the action that was performing a checkout. Everything is behaving as expected now. Just make sure to check any actions that you call and make sure they behave how you expect them to.