Add three synthesized Friendship PCS responses with ground truth

Covers all nine stress cases from #25, #15 and #16. The lowest bid is
disqualified on two missing health documents and the highest bid is
strongest on the SFA's own geographic-preference criterion, so a ranking
that cannot represent absence gets the field exactly backwards.

Deliberate traps: a planted $400 arithmetic error in a stated total, an
unverifiable total whose unit price lives only in the external Excel, an
unlabelled exception, a non-priceable exception that is really a conditional
withdrawal, and an answered-but-negative response.

Second schema finding, surfaced by the validator: R-B6C is a mandatory gate
that no response document can establish. Coverage over it is unknowable
rather than absent.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

corpus/friendship-pcs/responses/source/chesapeake-food-service.md

@@ -0,0 +1,118 @@
+# Chesapeake Food Service, Inc.
+## Proposal to Friendship Public Charter School — Food Items, 2021–2022
+
+1120 Ridgely Street, Baltimore, MD 21230
+Marcus Bell, Vice President — (410) 555-0188
+
+---
+
+### Executive Summary
+
+Chesapeake Food Service is a family-owned broadline distributor operating
+out of Baltimore since 1978. We serve roughly two hundred accounts across
+Maryland and the District, of which about thirty are schools, and we are
+pleased to offer Friendship Public Charter School the most competitive
+delivered pricing in this market.
+
+Our proposition is straightforward. We buy well, we run lean, and we pass
+that through. Where other distributors in this bid will layer on portal
+technology and account management structures that ultimately appear in the
+case price, we have chosen to compete on the number that matters. Over an
+eight-site network across a full school year, the difference is
+substantial, and it is money that returns directly to the meal programme.
+
+Our business license and certificate of occupancy are enclosed, along with
+two years of audited financial statements prepared by Hanlon & Reeve LLP.
+The debarment, price determination and lobbying certifications are signed
+and enclosed, as are the equal opportunity and clean air and water
+certifications. Insurance is carried at two million per occurrence and four
+million aggregate and a certificate naming Friendship Public Charter School
+as additional insured is enclosed.
+
+We are committed to student nutrition and to the communities we serve, and
+we believe strongly that a school food programme succeeds or fails on
+consistency of supply rather than on marketing. That is the value we bring.
+
+### Pricing
+
+Our pricing is submitted separately on the Excel schedule provided.
+
+We price at a flat delivered unit cost per case with no volume tiers and no
+rebate mechanism, because we have found that banded pricing chiefly serves
+to make comparison difficult and to defer benefit to year end. Our number
+is our number from day one.
+
+Delivered case pricing is applied as quoted plus a per-stop delivery charge
+which varies with the frequency requested. At two deliveries per week per
+site, the charge is $34.00 per stop. At three per week it falls to $28.50
+per stop, and at four or more it falls to $24.00 per stop. Sites may elect
+different frequencies and may change frequency with two weeks' notice.
+
+At the estimated volume stated in the solicitation and assuming three
+deliveries weekly to each of the eight sites across a one hundred and
+eighty day calendar, our base year total bid cost is five hundred and
+forty-one thousand, two hundred and eighty dollars ($541,280).
+
+Prices are held firm through the base year. We would ask only for relief
+under the economic price adjustment provision in the event of a commodity
+movement exceeding eight percent, on the same published index basis
+contemplated in the solicitation.
+
+### Method of Approach and Implementation
+
+We would begin with a site survey of all eight locations in the two weeks
+following award, walking each receiving area with the site's authorised
+designee to confirm the delivery window, the receiving point and the
+storage capacity. Our experience is that most transition problems are
+receiving problems rather than supply problems, and they are best solved
+before the first delivery rather than after.
+
+Product is packed to USDA standards throughout. We have not historically
+found that schools require pack size changes from our standard
+configurations, but we would accommodate reasonable requests where our
+suppliers can support them.
+
+On nutritional documentation, our category managers hold CN labels and
+formulation statements for the school product range and provide these on
+request. We can supply these for any item in the proposed catalogue,
+typically within two business days of a request.
+
+We participate in the USDA Foods programme in Maryland and would work with
+the SFA to make appropriate use of entitlement, though we would note that
+our processing relationships are stronger in the protein categories than
+in fruit and vegetable. We think it right to be plain about that rather
+than to overstate it.
+
+As to local sourcing, Chesapeake buys from the Maryland and Delmarva
+growing region in season and has done so throughout its history. We are
+proud of those relationships. We would expect a meaningful proportion of
+produce delivered between June and October to originate within the region.
+
+We maintain a pest management programme at our Baltimore facility under
+contract with a licensed applicator, serviced monthly.
+
+### Bidder's Experience, Expertise and Reliability
+
+Forty-three years in continuous operation under the same family ownership
+is, we would suggest, its own evidence of dependability. We have never
+failed to complete work awarded to us and we have never been terminated for
+cause.
+
+We deliver on time. Our internal measurement for the last school year was
+in the high nineties by percentage, and we are comfortable being held to
+that standard contractually.
+
+Our staff know the USDA meal pattern requirements and the District's
+Healthy Schools Act obligations, and several of our account team have
+worked with DC schools for more than a decade.
+
+We would provide a single point of contact for the network with escalation
+directly to the undersigned. We do not operate an ordering portal; orders
+are placed by telephone or email to a named person, which our customers
+tell us they prefer.
+
+Three references are provided in the questionnaire, all Maryland school
+accounts.
+
+We appreciate the opportunity and would welcome the chance to discuss any
+element of this proposal with the committee.